Bulb Preclearance Program

Identification Manual
Some processes, equipment, and materials described in this manual may be patented. Inclusion in this 

manual does not constitute permission for use from the patent owner. The use of any patented invention in 

the performance of the processes described in this manual is solely the responsibility of the user. APHIS 

does not indemnify the user against liability for patent infringement and will not be liable to the user or to any 

third party for patent infringement.

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When using pesticies, read and follow all label instructions.

First Edition Issued 2011
10/2011-01 Bulb Identification Manual LOF-1

Bulb 

Identification 

Figures

Figure 2-1 Corm Sketch 2-2

Figure 2-2 Corm with Tunic Removed 2-3

Figure 2-3 Stages of Development of Gladiolus Corm 2-3

Figure 2-4 Acidanthera 2-5

Figure 2-5 Stromatinia gladioli on Acidanthera 2-6

Figure 2-6 Babiana 2-7

Figure 2-7 Brodiaea 2-9

Figure 2-8 Rhodococcus fascians on Brodiaea 2-10

Figure 2-9 Colchicum 2-11

Figure 2-10 Fusarium on Colchicum 2-12

Figure 2-11 Ditylenchus destructor on Colchicum. 2-13

Figure 2-12 Urocystis colchici on Colchicum 2-13

Figure 2-13 Crocosmia 2-15

Figure 2-14 Fusarium on Crocosmia 2-16

Figure 2-15 Penicillium gladioli on Crocosmia 2-17

Figure 2-16 Crocus 2-18

Figure 2-17 Mechanical Damage on Crocus 2-19

Figure 2-18 Aphelenchoides subtenuis on Crocus 2-20

Figure 2-19 Ditylenchus destructor on Crocus 2-21

Figure 2-20 Fusarium oxysporum on Crocus 2-21

Figure 2-21 Penicillium gladioli on Crocus 2-22

Figure 2-22 Botrytis croci on Crocus 2-22

Figure 2-23 Stromatinia gladioli on Crocus 2-23

Figure 2-24 Urocystis gladiolicola on Crocus 2-24

Figure 2-25 Uromyces croci on Crocus 2-24

Figure 2-26 Freesia 2-25

Figure 2-27 Fusarium on Freesia 2-26

Figure 2-28 Fusarium Infection 2-27

Figure 2-29 Symptoms in Freesia That May or May Not Be Those of 

Fusarium 2-28

Figure 2-30 Aspergillus on Freesia 2-29

Figure 2-31 Erwinia on Freesia 2-30

Figure 2-32 Rhodococcus fascians on Freesia 2-31

Figure 2-33 Stromatinia gladioli on Freesia 2-31

Figure 2-34 Thrips on Freesia 2-32

Figure 2-35 Gladiolus 2-33

Figure 2-36 Botrytis on Gladiolus 2-34

Figure 2-37 Fusarium oxysporum on Gladiolus 2-35

Figure 2-38 Mechanical Damage on Gladiolus 2-36
Figures

 

LOF-2 Bulb Identification Manual 10/2011-01

Figure 2-39 Penicillium gladioli on Gladiolus 2-37

Figure 2-40 Thrip damage on Gladiolus 2-38

Figure 2-41 Curvularia trifolii on Gladiolus 2-38

Figure 2-42 Frost Damage on Gladiolus 2-39

Figure 2-43 Kirkstip on Gladiolus 2-39

Figure 2-44 Rhizoctonia violaceae on Gladiolus 2-40

Figure 2-45 Septoria gladioli on Gladiolus 2-40

Figure 2-46 Ditylenchus destructor on Gladiolus nanus 2-41

Figure 2-47 Meloidogyne on Gladiolus 2-42

Figure 2-48 Pseudomonas gladioli on Gladiolus 2-42

Figure 2-49 Pseudomonas marginata on Gladiolus 2-43

Figure 2-50 Rhodococcus fascians on Gladiolus 2-43

Figure 2-51 Stromatinia gladioli on Gladiolus 2-44

Figure 2-52 Urocystis gladiolicola on Gladiolus 2-45

Figure 2-53 Ixia 2-46

Figure 2-54 Sparaxis 2-48

Figure 3-1 Sketch of a Common Perennial, Grass 3-4

Figure 3-2 Growing Media and Weeds in Perennials 3-5

Figure 3-3 Aconitum 3-6

Figure 3-4 Meloidogyne on Aconitum 3-7

Figure 3-5 Aphelenchoides on Aconitum 3-8

Figure 3-6 Verticillium on Aconitum 3-9

Figure 3-7 Agapanthus 3-10

Figure 3-8 Anemone japonica 3-12

Figure 3-9 Meloidogyne hapla on Anemone 3-13

Figure 3-10 Aquilegia 3-14

Figure 3-11 Aruncus 3-16

Figure 3-12 Meloidogyne hapla on Aruncus 3-17

Figure 3-13 Meloidogyne hapla on Aruncus 3-18

Figure 3-14 Astrantia major 3-19

Figure 3-15 Meloidogyne hapla on Astrantia 3-20

Figure 3-16 Campanula 3-21

Figure 3-17 Meloidogyne on Campanula lactiflora ‘Pouffe’ 3-22

Figure 3-18 Campanula lactiflora ‘Pouffe’ with Rhodococcus fascians 3-

23

Figure 3-19 Dicentra spectabilis (left); Dicentra formosa (right) 3-24

Figure 3-20 Penicillium on Dicentra stabilis 3-25

Figure 3-21 Dicentra formosa with Storage Rot 3-26

Figure 3-22 Echinacea ‘Sunrise’ 3-27

Figure 3-23 Rhodococcus on Echinacea ‘Mango Meadowbrite’ 3-28

Figure 3-24 Epimedium perralchium cv. Frohn Leitneri 3-29

Figure 3-25 Epimedium youngianum 3-30

Figure 3-26 Epimedium with Pratylenchus penetrans 3-31

Figure 3-27 Epimedium youngianum with Pratylenchus penetrans 3-32

Figure 3-28 Eremurus 3-33

Figure 3-29 Storage Rot on Eremurus 3-34

Figure 3-30 Eryngium 3-35

Figure 3-31 Meloidogyne on Eryngium alpinum 3-36
 Figures

 

10/2011-01 Bulb Identification Manual LOF-3

Figure 3-32 Two Types of Geranium 3-37

Figure 3-33 Meloidogyne on Three Different Varieties of Geranium 3-38

Figure 3-34 Rhodococcus on Geranium 3-39

Figure 3-35 Geranium sanguineum with Anomalous Galling on 

Rhizomatous Roots 3-40

Figure 3-36 Heuchera 3-41

Figure 3-37 Heuchera ‘Plum Pudding’ with Meloidogyne hapla 3-42

Figure 3-38 Close-up of Swellings Caused by Meloidogyne hapla and 

Proliferation of Abnormal, Fine Rootlets 3-43

Figure 3-39 Hosta 3-44

Figure 3-40 Meloidogyne Infection Causing Swollen Root Tips and Densely 

Bushy Root System 3-45

Figure 3-41 Stunted Root Tips and Abnormal Root Growth Caused by 

Meloidogyne 3-45

Figure 3-42 Storage Rot on Hosta with Early Botrytis Infection on Roots and 

Apex 3-46

Figure 3-43 Botrytis Infection on Hosta Roots 3-47

Figure 3-44 Pratylenchus penetrans on Hosta 3-47

Figure 3-45 Incarvillea 3-48

Figure 3-46 Phytophthora sp. on Incarvillea 3-49

Figure 3-47 Phytophthora sp. on Incarvillea Showing Longitudinal Sections 

of Infected Roots 3-49

Figure 3-48 Liatris 3-51

Figure 3-49 Verticillium on Liatris 3-52

Figure 3-50 Botrytis on Liatris with White/Gray Mycelium 3-53

Figure 3-51 Ditylenchus destructor on Liatris calilepsis 3-53

Figure 3-52 Ligularia 3-54

Figure 3-53 Meloidogyne on Ligularia 3-55

Figure 3-54 Meloidogyne on Ligularia 3-55

Figure 3-55 Early Stages of Botrytis Rot on Ligularia 3-56

Figure 3-56 Papaver 3-57

Figure 3-57 Storage Rot on Papaver 3-58

Figure 3-58 Agrobacterium tumefasciens on Papaver 3-59

Figure 3-59 Meloidogyne hapla on Roots of Papaver 3-60

Figure 3-60 Phlox 3-61

Figure 3-61 Meloidogyne on Phlox 3-62

Figure 3-62 Meloidogyne on Phlox 3-63

Figure 3-63 Pratylenchus penetrans on Phlox 3-64

Figure 3-64 Rhodococcus fascians on Phlox 3-64

Figure 3-65 Platycodon 3-66

Figure 3-66 Storage Rot on Platycodon 3-68

Figure 3-67 Pulmonaria 3-69

Figure 3-68 Meloidogyne on Pulmonaria 3-70

Figure 3-69 Rudbeckia 3-71

Figure 3-70 Salvia nemorosa ‘Sensation’ (left); Salvia pratensis ‘Madeline’ 

(right) 3-73

Figure 3-71 Tradescantia 3-75

Figure 3-72 Veronica 3-77
Figures

 

LOF-4 Bulb Identification Manual 10/2011-01

Figure 3-73 Meloidogyne on Veronica 3-78

Figure 3-74 Rhodococcus fascians on Veronica 3-79

Figure 4-1 Iris Rhizome Sketch 4-2

Figure 4-2 Astilbe 4-3

Figure 4-3 Meloidogyne on Astilbe 4-4

Figure 4-4 Canna 4-6

Figure 4-5 Botrytis cineria on Canna 4-7

Figure 4-6 Convallaria majalis 4-8

Figure 4-7 Convallaria with Pratylenchus convallariae 4-9

Figure 4-8 Hemerocallis 4-10

Figure 4-9 Pratylenchus penetrans on Hemerocallis 4-11

Figure 4-10 Iris germanica (left), Iris siberica (right) 4-12

Figure 4-11 Pratylenchus penetrans on Iris 4-13

Figure 4-12 Two Varieties of Paeonia 4-14

Figure 4-13 Meloidogyne on Paeonia 4-15

Figure 4-14 Swellings on Paeonia Roots 4-15

Figure 4-15 Penicillium on Paeonia 4-16

Figure 4-16 Paeonia with Rhodococcus fascians 4-17

Figure 4-17 Zantedeschia 4-18

Figure 4-18 Erwinia carotovora on Zantedeschia 4-19

Figure 5-1 Sketch of a Lateral View and a Cross Sectional View of a True 

Bulb 5-3

Figure 5-2 Sketch of a True Bulb, the Lily 5-4

Figure 5-3 Steps in the Life Cycle of a True Bulb 5-4

Figure 5-4 Allium (top to bottom): Allium karataviense; A. 

sphaerocephalon; A. moly; A. neapolitanum 5-6

Figure 5-5 Fusarium oxysporum on Allium 5-7

Figure 5-6 Mechanical Damage on Different Varieties of Allium 5-8

Figure 5-7 Mechanical Damage on Allium moly 5-8

Figure 5-8 Penicillium on Allium 5-9

Figure 5-9 Aphelencoides subtenuis on Allium 5-9

Figure 5-10 Aspergillus on Allium moly 5-10

Figure 5-11 Aceria tulipae Symptoms on Allium 5-10

Figure 5-12 Ditylenchus dipsaci on Allium 5-11

Figure 5-13 Gummosis on Allium 5-12

Figure 5-14 Sclerotium cepivorum on Allium 5-12

Figure 5-15 Camassia leichtlinii 5-13

Figure 5-16 Camassia with Ditylenchus destructor 5-14

Figure 5-17 Chionodoxa 5-15

Figure 5-18 Penicillium on Chionodoxa 5-16

Figure 5-19 Ditylenchus dipsaci on Chionodoxa 5-17

Figure 5-20 Fritillaria imperialis (top left); F. uva vulpis (top right); F. 

meleagris (bottom) 5-18

Figure 5-21 Fusarium on F. meleagris (top) and F. imperialis (bottom) 5-

20

Figure 5-22 Mechanical Damage on Fritillaria imperialis 5-21

Figure 5-23 Penicillium on Fritillaria uva vulpis 5-21

Figure 5-24 Galanthus nivalis (top); G. elwesii (middle); G. woronowi 
 Figures

 

10/2011-01 Bulb Identification Manual LOF-5

(bottom) 5-22

Figure 5-25 Fusarium on Galanthus nivalis (tunic removed) 5-23

Figure 5-26 Botrytis galanthina on Galanthus 5-23

Figure 5-27 Ditylenchus dipsaci on Galanthus nivalis (tunic removed) 5-

24

Figure 5-28 Galtonia 5-25

Figure 5-29 Fusarium on Galtonia 5-26

Figure 5-30 Hippeastrum 5-27

Figure 5-31 Stagonospora curtisii on Hippeastrum 5-29

Figure 5-32 Steneotarsonemus laticeps on Hippeastrum 5-30

Figure 5-33 Hyacinthus 5-32

Figure 5-34 Aspergillus niger on Hyacinthus Variety with White Tunic 5-

33

Figure 5-35 Erwinia carotovora on Hyacinthus 5-34

Figure 5-36 Hyacinthus with Penicillium 5-34

Figure 5-37 Fusarium on Hyacinthus 5-35

Figure 5-38 Rhodococcus on Hyacinthus 5-35

Figure 5-39 Cross Section of Hyacinthus Bulbs Showing Discolored Leaf 

Scales Caused by Infection of Ditylenchus dipsaci 5-36

Figure 5-40 Erwinia rhapontica on Hyacinthus 5-37

Figure 5-41 Thrip Damage Along Inner Scales on Hyacinth (outer leaf scales 

removed) 5-38

Figure 5-42 Xanthomonas on Hyacinthus 5-39

Figure 5-43 Iris: (top row) Iris danfordii; (bottom row) Iris reticulata 5-40

Figure 5-44 Advanced Infection of Fusarium on Iris 5-41

Figure 5-45 Penicillium on Iris 5-41

Figure 5-46 Aphid Damage on Iris 5-42

Figure 5-47 Ditylenchus destructor on Iris 5-43

Figure 5-48 Dreschslera iridis on Iris 5-43

Figure 5-49 Iris Bulbs Severely Infected with Mealybugs 5-44

Figure 5-50 Iris Bulbs with Phenacoccus avenae 5-44

Figure 5-51 Plodia interpunctella on Iris 5-45

Figure 5-52 Sclerotium wakkeri on Iris Bulbs 5-46

Figure 5-53 Different Varieties of Lilium 5-47

Figure 5-54 Lilium Bulbs Infected with Fusarium 5-48

Figure 5-55 Aphelenchoides on Lilium 5-49

Figure 5-56 Lilium with Penicillium Forming as a Result of Mechanical 

Damage 5-50

Figure 5-57 Rhizoglyphus robinii Symptoms on Lilium 5-50

Figure 5-58 Rhodococcus on Lilium 5-51

Figure 5-59 Botrytis cineria on Lilium 5-52

Figure 5-60 Lilium with Outer Scales Removed, Showing Characteristic 

Russeting and Live Adult Thrips 5-53

Figure 5-61 Muscari armeniaca (left); M. comosum “Plumosum” (right) 5-

54

Figure 5-62 Fusarium on Muscari armeniacum 5-55

Figure 5-63 Penicillium on Muscari armeniacum 5-55

Figure 5-64 Rhodococcus fascians on Muscari 5-56
Figures

 

LOF-6 Bulb Identification Manual 10/2011-01

Figure 5-65 Ditylenchus dipsaci on Muscari 5-56

Figure 5-66 Nose Rot on Muscari 5-57

Figure 5-67 Narcissus 5-58

Figure 5-68 Bruising on Narcissus 5-59

Figure 5-69 Fusarium on Narcissus 5-60

Figure 5-70 Steneotarsonemus laticeps on Narcissus 5-61

Figure 5-71 Aphelenchoides subtenuis on Narcissus Showing Basal Plate 

Beginning to Separate from Bulb 5-62

Figure 5-72 Botrytis narcissicola on Narcissus 5-62

Figure 5-73 Ditylenchus dipsaci on Narcissus 5-63

Figure 5-74 “Horse Teeth” on Narcissus 5-64

Figure 5-75 Sunburn on Narcissus 5-65

Figure 5-76 Bulb Fly in Narcissus 5-66

Figure 5-77 Ornithogalum 5-67

Figure 5-78 Fusarium on Ornithogalum 5-68

Figure 5-79 Penicillium on Ornithogalum nutans 5-69

Figure 5-80 Oxalis adenophylla (top left); O. deppei (top right); O. 

triangularis (bottom) 5-70

Figure 5-81 Puschkinia libanotica 5-72

Figure 5-82 Penicillium on Puschkinia libanotica 5-73

Figure 5-83 Ditylenchus dipsaci on Puschkinia libanotica 5-74

Figure 5-84 Scilla 5-75

Figure 5-85 Scilla with Penicillium 5-76

Figure 5-86 Aspergillus on Scilla peruviana 5-77

Figure 5-87 Sclerotinia bulborum on Scilla siberica 5-78

Figure 5-88 Xanthomonas campestris pv hyacinthi on Scilla 5-78

Figure 5-89 Sprekelia 5-79

Figure 5-90 Longitudinal Section of Sprekelia Bulb Showing Characteristic 

Red Discoloration of Scales Affected by Steneotarsonemus 

laticeps 5-80

Figure 5-91 Tigridia 5-81

Figure 5-92 Tigridia with Fusarium 5-82

Figure 5-93 Ditylenchus destructor on Tigridia 5-83

Figure 5-94 Four Different Types of Tulipa 5-84

Figure 5-95 Fusarium oxysporum tulipae on Tulipa 5-85

Figure 5-96 Mechanical Damage on Tulipa 5-86

Figure 5-97 Penicillium on Damaged Areas of Tulipa 5-86

Figure 5-98 Aceria tulipae on Tulipa 5-87

Figure 5-99 Nose Rot on Tulipa 5-88

Figure 5-100 Chalking on Tulipa 5-89

Figure 5-101 Tulipa with Curtobacterium flaccumfasciens pv. oortii 5-90

Figure 5-102 Rhizoctonia solani on Tulipa 5-91

Figure 5-103 Sclerotinia bulborum on Tulipa 5-91

Figure 5-104 Aphids on Tulipa (note gray adult aphids) 5-92

Figure 5-105 Aspergillus on Tulipa 5-92

Figure 5-106 Botrytis tulipae on Tulipa 5-93

Figure 5-107 Ditylenchus destructor on Tulipa 5-93

Figure 5-108 Ditylenchus dipsaci on Tulipa 5-94
 Figures

 

10/2011-01 Bulb Identification Manual LOF-7

Figure 5-109 Gummosis on Tulipa 5-94

Figure 5-110 “Horse Teeth” on Tulipa 5-95

Figure 5-111 Pseudo-kirkstip on Tulipa 5-95

Figure 5-112 Septocylindrium on Tulipa 5-96

Figure 5-113 Skin Diseases in Tulipa 5-97

Figure 5-114 Skin Disease “Blue Growth” in Tulipa 5-97

Figure 5-115 Suffocation Disorders in Tulipa 5-98

Figure 5-116 Zephyranthes 5-99

Figure 6-1 Sketch of a Begonia Tuber 6-2

Figure 6-2 Anemone coronaria 6-3

Figure 6-3 Arum italicum 6-5

Figure 6-4 Advanced Stages of Erwinia aroidea Infection on Arum 

italicum 6-6

Figure 6-5 Begonia 6-7

Figure 6-6 Cross Sections of Begonia Showing Examples of Storage Rot 

6-8

Figure 6-7 Botrytis on Begonia 6-9

Figure 6-8 Erwinia chrysanthii on Begonia 6-9

Figure 6-9 Three Different Species of Cyclamen 6-10

Figure 6-10 Botrytis cinerea on Cyclamen 6-11

Figure 6-11 Dahlia 6-12

Figure 6-12 Dahlia with Characteristic Swellings of Meloidogyne 6-13

Figure 6-13 Examples of Dahlia Infected with R. fasciens 6-14

Figure 6-14 Dahlia with Top Rot 6-14

Figure 6-15 Agrobacterium tumefasciens on Dahlia 6-15

Figure 6-16 Frost Damage on Dahlia 6-15

Figure 6-17 Penicillium on Dahlia 6-16

Figure 6-18 Ditylenchus destructor on Dahlia 6-17

Figure 6-19 Erwinia on Dahlia 6-17

Figure 6-20 Advanced Stage of Sclerotinia sclerotiorium Infection in Dahlia 

6-18

Figure 6-21 Eranthis 6-19

Figure 6-22 Gloriosa 6-21

Figure 6-23 Erwinia and Phytophthora on Gloriosa 6-22

Figure 6-24 Penicillium on Gloriosa Tubers 6-22

Figure 6-25 Rhizoglyphus in Gloriosa 6-23

Figure 6-26 Rhodococcus on Gloriosa 6-23

Figure 6-27 Ranunculus 6-24
Figures

 

LOF-8 Bulb Identification Manual 10/2011-01
10/2011-01 Bulb Identification Manual LOT-1

Bulb 

Identification 

Tables

Table 1-1 Categories of Pests and Diseases 1-2

Table 1-2 Procedures to Report a Problem with a Manual 1-6

Table 2-1 Pest Risk Ratings for Corms 2-4

Table 3-1 Pest Risk Ratings for Perennials 3-5

Table 4-1 Pest Risk Ratings for Rhizomes 4-2

Table 5-1 Pest Risk Ratings for True Bulbs 5-5

Table 6-1 Pest Risk Ratings for Tubers 6-2
Tables

 

LOT-2 Bulb Identification Manual 10/2011-01
10/2011-01 Bulb Identification Manual Acknowledgements-1

Bulb 

Identification 

Acknowledgements

Thank you to the following Dutch inspectors for technical information and for 

bringing material in from their inspections: P. Bos, J. Ooteman, A. Ruiter, A. 

Schrooder, and P. van Steyn.

The Bloembollenkeuringsdeinst (BKD), the Applied Plant Research Station in 

Lisse (PPO), and the Dutch plant protection service (the new Food Safety 

Authority or nVWA) provided numerous photographs.

Thank you to T. Overdevest of the BKD for the use of his personal photos, for 

technical advice, and for reviewing the final draft of the manual.

G. van Grinsven (Dutch General Inspection Service for Agricultural Seed and 

Seed Potatoes (NAK)) provided photos from his personal collection and 

technical information on corms.

Photographs were also obtained from the library of the late J. Heuperman.
Acknowledgements

 

Acknowledgements-2 Bulb Identification Manual 10/2011-01
10/2011-01 Bulb Identification Manual 1-1

Chapter

1

Introduction

Contents

Purpose 1-1

Scope 1-1

Conventions 1-2

Advisories 1-2

Boldface 1-3

Bullets 1-3

Change Bar 1-3

Chapters 1-3

Contents 1-3

Control Data 1-4

Examples 1-4

Footnotes 1-4

Heading Levels 1-4

Hyperlinks to Tables, Figures, and Headings 1-5

Indentions 1-5

Italics 1-5

Numbering Scheme 1-5

Transmittal Number 1-5

Using the Manuals 1-6

Reporting Problems With or Suggestions For the Manuals 1-6

Manual Updates 1-6

Purpose

This Bulb Indentification Manual is intended as a reference for officers who 

will inspect bulbs for shipment to North America. 

Scope

This is not an encyclopedic account of all the bulbs (including corms, 

rhizomes, and tubers) and perennials covered by the preclearance program. 

Out of more than 300 genera that are in the program, only about 70 most 

important ones in terms of volume are included in this manual. Many were 

selected to show the great diversity of the material exported through the 

program. 
Introduction

Conventions

1-2 Bulb Identification Manual 10/2011-01

The pests and diseases described for each genus are only those that are 

currently being intercepted by the Dutch inspection services and the 

preclearance team. They are categorized into three groups:

The term “pest” here includes insect pests, diseases, physiological disorders 

and any other reason for phytosanitary rejection. Most of the insect pests that 

attack the plant during the growing season are not included as they are 

eliminated during washing. Furthermore, many pests and diseases are culled 

out by the exporter and are never seen during the phytosanitary inspections. 

These are not included in this manual. It is also important to note that because 

of improved horticultural practices, many pests and diseases that were 

common 20 years ago are never seen today.

Conventions

Conventions are established by custom and are widely recognized and 

accepted. Major conventions used in MU manuals follow.

Advisories

Advisories are use throughout MU manuals to bring important information to 

the user’s attention. Please carefully review each advisory. The definitions 

coincide with the American National Standards Institute (ANSI) with the goal 

of making the warnings easy to recognize and understand, thus limiting the 

human and dollar cost of foreseeable errors and accidents,1

 and are in the 

format shown below.

Table 1-1 Categories of Pests and Diseases

Common Pests Those that are commonly intercepted

Rare Pests Those that are intercepted only once or twice a season

Other Pests Those that are intercepted less frequently

1 TCIF Guideline, Admonishments (Safety-Related Warning Message), TCIF-99-021 Issue 1, p.4

NOTICE

! CAUTION

! WARNING
Introduction

Conventions

10/2011-01 Bulb Identification Manual 1-3

Two significant changes in current warning messages are as follows:

CAUTION, WARNING, and DANGER should now be used only for risks 

to personal safety, (in compliance with ANSI and the Occupational Safety 

and Health Administration (OSHA))

Presentation has been standardized around the colors and symbols 

prescribed by ISO and the layouts and typography prescribed by ANSI2

Boldface

Boldface type is used to emphasize important words throughout MU manuals. 

These words include, but are not limited to: cannot, do not, does not, except, 

lacks, must, neither, never, nor, not, only, other than.

Bullets

Bulleted lists indicate that there is no order of priority to the information being 

listed. Bulleted lists should always be in alphabetical order.

Change Bar

A black change bar is used to indicate a change appearing on a revised page. 

Unfortunately, change bars do not always appear when text is merely deleted.

Chapters

This manual contains the following chapters:

1. Chapter 1: Introduction

2. Chapter 2: Corms

3. Chapter 3: Perennials

4. Chapter 4: Rhizomes

5. Chapter 5: True Bulbs

6. Chapter 6: Tubers

7. Chapter 7: Glossary

8. Index

Contents

Every chapter has a table of contents listing only the first- and second-level 

headings within the chapter.

! DANGER

2 Id.
Introduction

Conventions

1-4 Bulb Identification Manual 10/2011-01

Control Data

Control data is located at the top and bottom of each page to help manual users 

keep track of where they are in the manual ad to be aware of updates to specific 

chapters, appendixes, etc. At the top of each page is the chapter title and firstlevel heading for that page. At the bottom of each page is the transmittal 

number (month/year-issue or edition number), manual title, and page number.

Examples

Examples are used to clarify a point by applying it to a real-world situation. 

Examples always appear in a box as a means of visually separating them from 

the other information contained on the page.

Footnotes

Footnotes comment on or cite a reference to text and are referenced by a 

number. The footnotes used in MU manuals include general text footnotes, 

figure footnotes, and table footnotes.

General text footnotes are located at the bottom of the page after a thin green 

line half the width of the page and flow numerically throughout a chapter.

When space allows, figure and table footnotes are located directly below the 

associated figure or table. However, multipage figures and tables, or figures 

and tables covering the entire length of a page cannot accommodate footnote 

numbers and footnote text on the same page. If a table or figure continues 

beyond one page, the associated footnotes will appear on the page following 

the end of the figure or table. Each table’s footnotes are individually 

numbered, e.g., a chapter may have three tables and within each table is a 

single footnote, then each footnote will be indicated with the number 1.

Heading Levels

Within each chapter there are four heading levels. The first-level heading is 

indicated by a horizontal line across both the left and right columns with the 

heading language across the left and right columns directly underneath. The 

body text after a first-level heading is located inside the margined text area, 

one line after the heading language. The second- and third-level headings are 

inside the margined text area with the body of text following underneath. The 

fourth-level heading is inside the margined text area followed by a period and 

leading into the text.

EXAMPLE Examples are graphically placed boxes within the text as a means of 

visually separating information from other infromation contained on 

the page. MU examples always appear in a box like this.
Introduction

Conventions

10/2011-01 Bulb Identification Manual 1-5

Hyperlinks to Tables, Figures, and Headings

Tables, figures, and headings are cross-referenced in the body of the manual 

and are in hyptertext (blue) font.

Indentions

MU manuals indent content information, lengthy quotes, and entry 

requirements summarized from the Code of Federal Regulations (CFRs), 

import permits, or policies.

Italics

The following items are italicized throughout MU manuals.

Cross-references to headings and figure/table titles

Publication names

Scientific names of commodities

Numbering Scheme

A two-level or three-level numbering scheme is used in MU manuals. In twolevel numbering, the first number represents the chapter and the second 

number represents the page, table, or figure number. In three-level numbering, 

the first number represents the chapter, the second number represents the 

section, and the third number represents the page, table, or figure number. 

Dashes are used in page numbering to differentiate page numbers from decimal 

points.

Transmittal Number

The transmittal number contains the month, year, and consecutively issued 

number (beginning with -01 for the first edition and increasing consecutively 

for each update to the chapter or section). The transmittal number is only 

changed when the specific front matter, chapter, section, or back matter is 

updated. If no changes are made to a specific chapter or section, the transmittal 

number for that chapter or section remains unchanged. The transmittal number 

only changes for the entire manual when a new edition is issued or changes are 

made to the entire manual.

EXAMPLE See Reporting Problems With or Suggestions For the Manuals to 

determine where to report report problems with the manual.

EXAMPLE 06/2011-01 is the transmittal number for this update and is located in 

the control data in the footer area of the pages in this volume.

06 is the month the manual/update was issued.

2011 is the year the manual/update was issued.

01 is the manuals edition number (the original edition).
Introduction

Using the Manuals

1-6 Bulb Identification Manual 10/2011-01

Using the Manuals

Review the TOC of a manual to get a feel for the scope of covered material. 

Use the TOC in each chapter (miniTOC) to find the needed information. If the 

TOC or miniTOC are not specific enough, turn to the index to find the topic 

and corresponding page number.

Reporting Problems With or Suggestions For the Manuals

MU manuals provide users with information to determine where to report 

problems, disagreements, or improvements that directly affect the contents of a 

manual. An example follows:

Manual Updates

The online manuals attempt to capture the most up-to-date information. Most 

MU manuals are electronically issued on the APHIS Web site.

Table 1-2 Procedures to Report a Problem with a Manual

If you: Then:

Are not able to access the online manual CONTACT Josie Cooley by email at 

josie.cooley@aphis.usda.gov Have a situation that requires an immediate 

response regarding a procedure

Have a suggestion for improving the formatting of the content (design, layout, composition), grammar, or spelling
10/2011-01 Bulb Identification Manual 2-1

Chapter

2

Corms

Contents

Introduction 2-2

Identification Procedure 2-4

Acidanthera (Gladiolus callicanthus) 2-5

Pest Risk Rating 2-5

Similar Looking Corms 2-5

Inspection Procedures 2-6

Pests 2-6

Babiana 2-7

Pest Risk Rating 2-7

Similar Looking Corms 2-7

Inspection Procedures 2-7

Pests 2-8

Brodiaea 2-9

Pest Risk Rating 2-9

Similar Looking Corms 2-9

Inspection Procedures 2-10

Pests 2-10

Colchicum 2-11

Pest Risk Rating 2-11

Similar Looking Corms 2-11

Inspection Procedures 2-11

Pests 2-12

Crocosmia 2-15

Pest Risk Rating 2-15

Similar Looking Corms 2-15

Inspection Procedures 2-15

Pests 2-16

Crocus 2-18

Pest Risk Rating 2-18

Similar Looking Corms 2-18

Inspection Procedures 2-18

Pests 2-19

Freesia 2-25

Pest Risk Rating 2-25

Similar Looking Corms 2-25

Inspection Procedures 2-25

Pests 2-25
Corms

Introduction

2-2 Bulb Identification Manual 10/2011-01

Gladiolus 2-33

Pest Risk Rating 2-33

Similar Looking Corms 2-33

Inspection Procedures 2-33

Pests 2-34

Ixia 2-46

Pest Risk Rating 2-46

Similar Looking Corms 2-46

Inspection Procedures 2-46

Pests 2-47

Sparaxis 2-48

Pest Risk Rating 2-48

Similar Looking Corms 2-48

Inspection Procedures 2-48

Pests 2-49

Introduction

This section provides descriptions, photographs, inspection procedures, and 

major pests of a variety of genera of corms. Corms are underground, upright, 

enlarged stems that are topped with buds. They are 80–100 percent covered 

with a tunic which are the remains of the old leaf bases, and have nodes with 

axillary buds.

Figure 2-1 Corm Sketch
Corms

Introduction

10/2011-01 Bulb Identification Manual 2-3

When a corm starts to grow, the bud expands and new roots emerge from the 

base of the bud (Stage 1). Nutrients are taken up from the old corm to 

supplement the growth of the new corm on top of the old one (Stage 2). The 

old corm shrivels and becomes a mummy. Occasionally, this mummy will 

remain attached to the corm that is presented for shipment. In gladiolus, rootlike structures emerge from the base and expand to form tiny new corms or 

cormlets (Stage 3).

Figure 2-2 Corm with Tunic Removed

Figure 2-3 Stages of Development of Gladiolus Corm 
Corms

Introduction

2-4 Bulb Identification Manual 10/2011-01

The information in this chapter includes the pest risk rating for each bulb. The 

ratings are:

Identification Procedure

Determine the length of the corm you are identifying. Compare it with the 

photographs in this chapter and select the description that fits your corm. Each 

description includes inspection procedures and pests of concern.

Table 2-1 Pest Risk Ratings for Corms

Pest Risk Rating

1-2 Very low risk. Verify the genus in the shipment. Inspect if time is available

3-4 Low risk. Inspect if time is available

5-6 Moderate risk. Provide normal inspection

7-8 High risk. Inspect thoroughly

9-10 Very high risk. Inspect very thoroughly
Corms

Acidanthera (Gladiolus callicanthus)

10/2011-01 Bulb Identification Manual 2-5

Acidanthera (Gladiolus callicanthus)

Acidanthera produces a small to medium sized corm with a pinkish-beige, 

papery tunic with reticulations on the top half. The corm is conical shaped, 

often with a slight twist, and the tip slightly off-center. The flesh of the corm is 

cream colored with yellow node lines.

Pest Risk Rating

The pest risk rating for Acidanthera is 2–3.

Similar Looking Corms

Freesia show no reticulation on the tunic, and it is thinner and smaller.

Source: USDA-APHIS

Figure 2-4 Acidanthera
Corms

Acidanthera (Gladiolus callicanthus)

2-6 Bulb Identification Manual 10/2011-01

Inspection Procedures

1. Check consignment and verify lot.

2. Check for soil contamination and select abnormal corms for inspection.

3. Peel tunic back and look at flesh.

Pests

Common Pests

None

Rare Pests

Fusarium. Symptoms: Attacks the basal plate, causes depressed sunken lesions 

forming concentric rings. 

No photo available.

Other Pests

Botrytis. Symptoms: Pinpoint brown spots that radiate into the flesh, and will 

also infect areas besides the basal plate.

No photo available.

Stromatinia gladioli. Symptoms: Brown lesions with black sclerotia on the tunic. 

On the corm surface, lesions become sunken and usually turn black with 

slightly raised margins.

Source: PPO

Figure 2-5 Stromatinia gladioli on Acidanthera
Corms

Babiana

10/2011-01 Bulb Identification Manual 2-7

Babiana

Babiana are small, globose or teardrop shaped corms with a very small basal 

plate. The tunic is tough and fibrous, sometimes netted, longer than the corm 

itself and with a bronze sheen. There are splits along the veins.

Pest Risk Rating

The pest risk rating for Babiana is 2–3.

Similar Looking Corms

Because of its long, fibrous, bronzy tunic, Babiana corms are very distinctive. 

Crocosmia corms also have tunics that are longer than the corm itself, but the 

tunic of Babiana is softer than that of Crocosmia. Crocosmia corms usually 

bear persistent roots, whereas Babiana corms do not.

Inspection Procedures

1. Check consignment and verify lot.

2. Check for soil contamination and select abnormal corms for inspection.

3. Remove tunic and examine flesh.

Source: USDA-APHIS

Figure 2-6 Babiana
Corms

Babiana

2-8 Bulb Identification Manual 10/2011-01

Pests

Common Pests

None

Rare Pests

Fusarium. Symptoms: Attacks the basal plate area causing depressed, sunken 

lesions that form concentric rings.

No photo available.

Other Pests

Thrips. Symptoms: Fresh symptoms: sticky, mildly brown coloration, usually 

around the internodes.

No photo available.
Corms

Brodiaea

10/2011-01 Bulb Identification Manual 2-9

Brodiaea

Brodiaea corms are 0.5–0.75 inches (13–20 mm) in height and subglobose or 

broadly teardrop in shape. The corm is often asymmetrical due to the formation 

of cormlets and tends to angles on the sides. The tunic is cream colored, 

silvery-tan, grayish, or brown and fibrous with net-like at the base. The corm 

flesh is white and smooth. Many species formerly included in Brodiaea have 

been transferred to other genera, including Ipheion and Triteleia.

Pest Risk Rating

The pest risk rating for Brodiaea is 3.

Similar Looking Corms

Crocus is similar in size and shape.

Ixia has a tunic which is completely fibrous and woven, with flesh that is red to 

purple in color.

Sparaxis tunics are fibrous, with an open weave pattern. The skins or tunics are 

white.

Source: USDA-APHIS

Figure 2-7 Brodiaea
Corms

Brodiaea

2-10 Bulb Identification Manual 10/2011-01

Inspection Procedures

1. Check consignment and verify lot.

2. Check for soil contamination and select abnormal corms for inspection.

3. Peel off the tunic and examine the flesh.

Pests

Common Pests

None

Rare Pests

Fusarium. Symptoms: Attacks at the base causing depressed, sunken lesions 

that form concentric rings.

No photo available

Mechanical Injury. Symptoms: Causes small, shallow, dry callus that can be 

flicked off with a knife blade. Strictly a quality issue.

No photo available.

Rhodococcus fascians. Symptoms: Attacks at the base or where scales attach, 

causing small, thin, fan-like, fasciated scales or very small deformed bulblets. 

The variety ‘Queen Fabiola’ is especially susceptible.

Other Pests

None

Source: nVWA

Figure 2-8 Rhodococcus fascians on Brodiaea
Corms

Colchicum

10/2011-01 Bulb Identification Manual 2-11

Colchicum

Colchicum corms are very distinctive. It can be up to 3 inches (76 mm) or more 

in length, irregularly-shaped, convex on one side and flat on the other, with a 

foot-like projection from the base. The edge of the corm covering the foot is 

scalloped or fringed. The tunic is brown and leathery when mature and extends 

above the body of the corm to form a neck. The main corm has two small 

cormlets attached to it. One cormlet is attached to the foot, the other to the side 

of the main corm. The main corm has channels or grooves to receive the 

growing shoots of the small cormlets

Pest Risk Rating

Colchicum has a pest risk rating of 5–6.

Similar Looking Corms

There are no corms that resemble Colchicum.

Inspection Procedures

1. Check consignment and verify lot.

2. Check for soil contamination and select abnormal corms for inspection.

Source: USDA-APHIS

Figure 2-9 Colchicum
Corms

Colchicum

2-12 Bulb Identification Manual 10/2011-01

3. Examine tunics for disease symptoms.

4. Remove tunics and examine corm flesh.

5. Squeeze and examine basal plate

Pests

Common Pests

None

Rare Pests

Fusarium. Symptoms: Brown rot with distinct margins and accompanied by a 

musty, sour odor; usually basal. The left photo shows infection beginning at 

the sides of the corm. The right photo shows basal infections.

Other Pests

Ditylenchus detructor. Symptoms: Brown discoloration and streaking from the 

base of the corm. Basal plate eventually disintegrates, creating a depression at 

the base of the corm. Note the sunken base of the corm on the left in 

Figure 2-11.

Source: (left photo) BKD; (right photo) USDA-APHIS

Figure 2-10 Fusarium on Colchicum
Corms

Colchicum

10/2011-01 Bulb Identification Manual 2-13

Urocystis colchici. Symptoms: Raised black sori on the outer surface of the tunic.

Source: BKD

Figure 2-11 Ditylenchus destructor on Colchicum. 

Source: PPO

Figure 2-12 Urocystis colchici on Colchicum
Corms

Colchicum

2-14 Bulb Identification Manual 10/2011-01

Uromyces colchici. Symptoms: Rust colored spores forming ring-like areas with 

sori present only on the inside surface of tunics.

No photo available.
Corms

Crocosmia

10/2011-01 Bulb Identification Manual 2-15

Crocosmia

Crocosmia corms are globose, conical, or somewhat flattened and discoid in 

shape, 1–1.5 inches (25–38 mm) in diameter and up to 1.5 inches (38 mm) in 

height, with grayish-brown, coarse, fibrous tunic that is normally longer than 

the corm and persistent fibrous roots. A hard remnant of the previous year’s 

growth often remains at the base of the corm. With the tunic removed, the corm 

has prominent nodes.

Pest Risk Rating

Crososmia has a pest risk rating of 5.

Similar Looking Corms

Almost identical to Montbretia, which is not included in this manual. The 

corms of some varieties resemble those of Gladiolus.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select any abnormal corms for inspection.

Source: USDA-APHIS

Figure 2-13 Crocosmia
Corms

Crocosmia

2-16 Bulb Identification Manual 10/2011-01

3. Remove tunics and examine corm flesh and basal plate for disease 

symptoms.

Pests

Common Pests

None

Rare Pests

Fusarium. Symptoms: Black lesions at the nodes of the corm, resulting from the 

fungus entering the corm through the leaves. In cross-section of the corm, the 

infected vascular bundles radiating from the core are discolored and dark 

lesions are evident.

Source: BKD

Figure 2-14 Fusarium on Crocosmia1

1 Left photo: Note dark scab-like lesions along nodes of the corms. Right photo: Note discolored vascular bundles radiating from the core and brownish spotting of the corm.
Corms

Crocosmia

10/2011-01 Bulb Identification Manual 2-17

Other Pests

Botrytis. Symptoms: Circular lesions penetrating into the flesh.

No photo available

Source: USDA-APHIS

Figure 2-15 Penicillium gladioli on Crocosmia
Corms

Crocus

2-18 Bulb Identification Manual 10/2011-01

Crocus

Crocus is a pear-shaped to globose or subglobose corm 0.5–1.2 inches (12–30 

mm) in diameter and symmetrical or irregular in outline. The tunic is brown, 

fibrous, and coarsely or finely reticulate, netted or cloth-like, and membranous, 

papery, silky, or shell-like with overlapping scales. Some have annulate tunics 

that break up into rings around the corm, while others have tunics with 

longitudinal fibers. The interior of the corm is white and firm.

Pest Risk Rating

Crocus has a pest risk rating of 7–8.

Similar Looking Corms

The corms of different varieties of Crocus may resemble those of small 

Gladiolus.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal corms for inspection.

3. Examine the tunics for disease symptoms.

Source: USDA-APHIS

Figure 2-16 Crocus
Corms

Crocus

10/2011-01 Bulb Identification Manual 2-19

4. Examine for disease and especially the basal plate for nematode symptoms.

5. Examine corm flesh for disease symptoms.

Pests

Common Pests

Mechanical Damage. Symptoms: Abrasions, scars, discoloration due to damage 

sustained during harvest or during processing. A quality, non-quarantine issue. 

Purple coloration is normal for some varieties of this species.

Rare Pests

Aphelenchoides subtenuis. Symptoms: Damage concentrated around rootlets. 

Swollen, raised basal plate with discoloration spreading outward.

Source: USDA-APHIS

Figure 2-17 Mechanical Damage on Crocus 1

1 Top row shows scarring on thin-tunic Crocus vernus. The bottom row shows damage on C. 

chrysanthus. This species has thicker tunic and damage occurs where the tunic has been 

removed during harvest/processing.
Corms

Crocus

2-20 Bulb Identification Manual 10/2011-01

Ditylenchus destructor. Symptoms: Extensive core rotting of the corm flesh. 

Starts at the base and spreads outward as a discoloration and upward through 

the core.

Source: PPO

Figure 2-18 Aphelenchoides subtenuis on Crocus 1

1 Bottom right specimen is healthy. Note characteristic streaking from the basal plate in the other three specimens.
Corms

Crocus

10/2011-01 Bulb Identification Manual 2-21

Fusarium. Symptoms: Depressed chocolate brown to blackish lesions with 

white mycelia, usually around the basal plate.

Penicillium gladioli. Symptoms: Blue-green mold, usually secondary on damaged 

areas.

Source: T. Overdevest

Figure 2-19 Ditylenchus destructor on Crocus 1

1 Note discoloration spreading from the basal plate.

Source: (left photo) PPO; (right photo) nVWA

Figure 2-20 Fusarium oxysporum on Crocus
Corms

Crocus

2-22 Bulb Identification Manual 10/2011-01

Other Pests

Aphids. Symptoms: Usually with autumn flowering species. Emerging shoots 

can be sticky. Old aphid skins may be present.

No photo available

Botrytis croci. Symptoms: Dry rot with large sclerotia, especially along the 

nodes and penetrating the corm flesh.

Source: USDA-APHIS

Figure 2-21 Penicillium gladioli on Crocus

Source: PPO

Figure 2-22 Botrytis croci on Crocus
Corms

Crocus

10/2011-01 Bulb Identification Manual 2-23

Stromatinia gladioli. Symptoms: Brown to black, more or less circular lesions 

usually along the nodes, becoming sunken and often running together. Infected 

corm often becomes mummified and black.

Urocystis gladiolicola. Symptoms: Conspicuously raised black sori penetrating 

into the flesh.

Source: PPO

Figure 2-23 Stromatinia gladioli on Crocus
Corms

Crocus

2-24 Bulb Identification Manual 10/2011-01

Uromyces croci. Symptoms: Lesions forming on the surface of the corm under 

the tunic and penetrating into the interior. Occasionally, the infection may 

originate at the base of the corm.

Source: PPO

Figure 2-24 Urocystis gladiolicola on Crocus

Source: PPO

Figure 2-25 Uromyces croci on Crocus
Corms

Freesia

10/2011-01 Bulb Identification Manual 2-25

Freesia

Freesia corms are variable in shape and size depending on variety. In some 

varieties they are conical or ovoid, often with the tip bent to one side. In other 

varieties they could be almost oblong, somewhat flattened, nearly barrelshaped or globose. The fibrous tunic may be brownish or dirty-whitish with 

thin, diamond-shaped reticulations on the upper 1/2 to 3/4 of the corm. The 

basal plate is very small.

Pest Risk Rating

Freesia has a pest risk rating of 7.

Similar Looking Corms

Freesia corms are similar to Acidanthera and Gladiolus; however, Freesia

corms are generally more slender and smaller. The corms of some varieties 

resemble those of Gladiolus nanus.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal corms for inspection.

3. Remove tunic and examine corm flesh for disease and nematode 

symptoms.

Pests

Source: USDA-APHIS

Figure 2-26 Freesia
Corms

Freesia

2-26 Bulb Identification Manual 10/2011-01

Common Pests

Fusarium. Symptoms: Brown black discoloration of the core. Infection is not

restricted to base of corm. Superficial Fusarium-like symptoms often occur but 

the infections do not always affect the core of the corm. The causal agent may 

be another pathogen and Fusarium may or may not be present. Corms with 

these symptoms must be sent to the lab for determination.

Source: PPO

Figure 2-27 Fusarium on Freesia 1

1 Top row: characteristic symptoms of Fusarium. Bottom row: longitudinal sections of corms 

show internal damage caused by Fusarium.
Corms

Freesia

10/2011-01 Bulb Identification Manual 2-27

Source: USDA-APHIS

Figure 2-28 Fusarium Infection1

1 Fusarium infection in this variety of Freesia is characterized by distinct reddish-purple margins
Corms

Freesia

2-28 Bulb Identification Manual 10/2011-01

Rare Pests

Aspergillus. Symptoms: Black mold. Usually secondary on damaged areas.

Source: USDA-APHIS

Figure 2-29 Symptoms in Freesia That May or May Not Be Those of Fusarium
Corms

Freesia

10/2011-01 Bulb Identification Manual 2-29

Pseudokirkstip. Symptoms: Black spotting, bubbled surface of the corm with 

lesions in the interior. Symptoms are very similar to Cucumber Mosaic Virus 

and specimens must be sent to the laboratory for determination.

No photo available.

Other Pests

Erwinia chrysanthemi. Symptoms: Soft, mushy corms, deteriorating quickly; 

often with a foul odor.

Source: USDA-APHIS

Figure 2-30 Aspergillus on Freesia
Corms

Freesia

2-30 Bulb Identification Manual 10/2011-01

Penicillium. Symptoms: Blue-green mold.

No photo available.

Rhodococcus fascians. Symptoms: Fasciations at the base of the corm. In 

Figure 2-32, white scars near the base of the corm are due to mechanical 

damage.

Source: USDA-APHIS

Figure 2-31 Erwinia on Freesia
Corms

Freesia

10/2011-01 Bulb Identification Manual 2-31

Stromatinia gladioli. Symptoms: Brown to black somewhat circular lesions 

usually along nodes, becoming sunken and often running together.

Source: BKD

Figure 2-32 Rhodococcus fascians on Freesia

Source: PPO

Figure 2-33 Stromatinia gladioli on Freesia
Corms

Freesia

2-32 Bulb Identification Manual 10/2011-01

Thrips. Symptoms: Reddish or dark yellow speckling (russeting) of corm flesh. 

Live insects should be present.

Source: J. Heuperman

Figure 2-34 Thrips on Freesia
Corms

Gladiolus

10/2011-01 Bulb Identification Manual 2-33

Gladiolus

Gladiolus corms can be ovoid, globose or depressed globose, or somewhat 

conical in shape. They are usually medium sized, 1.5 inches (38 mm) in length 

and 2–2.5 inches (64 mm) in diameter, but small varieties can be 1 inch (25 

mm) in length and 1.5 inches (38 mm) in diameter. The basal plate is fairly 

large. Gladiolus tunic and corm vary in color from medium brown to red or 

purple. The tunic can be papery to firm, and coarsely or softly fibrous. Small 

flowering species sometimes lack tunics.

Pest Risk Rating

The pest risk rating for Gladiolus is 9–10.

Similar Looking Corms

Acidanthera is similar but has a different shape and tunic.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal corms for inspection.

3. Examine stem remnants for disease symptoms.

4. Examine corm flesh, especially around the basal plate, for insects, 

nematodes, and disease symptoms.

5. If the corm has broken dormancy, examine any growing points for aphids.

Source: USDA-APHIS

Figure 2-35 Gladiolus
Corms

Gladiolus

2-34 Bulb Identification Manual 10/2011-01

Pests

Common Pests

Botrytis. Symptoms: Slightly sunken, round, straw-colored to dark brown spots 

on any part of the corm, usually penetrating to the core. In other instances, 

decay can be general, varying in texture from soft and spongy to fibrous and 

firm and affecting significant portions of the corm. In advanced stages, corm is 

either a dark mass with pockets of whitish mycelia and black sclerotia, or hard 

and mummified.

Source: (top photo) PPO; (bottom photo) USDA-APHIS

Figure 2-36 Botrytis on Gladiolus
Corms

Gladiolus

10/2011-01 Bulb Identification Manual 2-35

Fusarium oxysporum. Symptoms: Dry, tan to blackish, depressed lesions often 

forming concentric rings as the infection expands. White to pink mycelia may 

be present. In some instances, only a few small lesions occur on surface, but 

the infection follows the vascular bundles into the core. In other instances, the 

lesions are larger and the rotted tissue may extend completely through the 

corm. Occasionally, dry-rot lesions occur only at the basal portion of the corm 

and do not penetrate into the core. Corm eventually becomes mummified 

during storage. In the top photo in Figure 2-37, the corm on the bottom right 

has become blackened and completely mummified. The bottom photo shows 

basal infection of Fusarium. Note the concentric growth rings of infection on 

the left corm.

Mechanical damage. Symptoms: Scarring and abrasions due to injury suffered 

during harvest and processing. This is a quality, not a quarantine issue. 

Secondary Penicillium may occur.

Source: USDA-APHIS

Figure 2-37 Fusarium oxysporum on Gladiolus
Corms

Gladiolus

2-36 Bulb Identification Manual 10/2011-01

Penicillium gladioli. Symptoms: Reddish-brown, sunken but superficial lesions 

often accompanied by blue-green mold with cream-colored sclerotia. Corm 

eventually becomes mummified during storage. A secondary infection on 

bruised or injured corms.

Source: USDA-APHIS

Figure 2-38 Mechanical Damage on Gladiolus
Corms

Gladiolus

10/2011-01 Bulb Identification Manual 2-37

Thrips. Symptoms: Brownish discoloration (russeting) usually at the 

internodes. If the infestation is recent, the affected areas would be somewhat 

sticky. In the photo below, the corm on the right is totally symptomatic. Except 

at the apex, bands of russeting are well-developed on the other two corms.

Source: USDA-APHIS

Figure 2-39 Penicillium gladioli on Gladiolus
Corms

Gladiolus

2-38 Bulb Identification Manual 10/2011-01

Rare Pests

Curvularia trifolii. Symptoms: Very irregular, depressed, brown to black lesions. 

Corms may develop a dark brown corky core rot.

Source: USDA-APHIS

Figure 2-40 Thrip damage on Gladiolus

Source: nVWA

Figure 2-41 Curvularia trifolii on Gladiolus
Corms

Gladiolus

10/2011-01 Bulb Identification Manual 2-39

Frost Damage. Symptoms: Corm becomes soft, spongy, and discolored. The 

photo below shows the top view of the corm on the left, and a cross-section on 

the right.

Kirkstip. Symptoms: Black scabs on the exterior and small lesions on the 

interior of the corm. The photo below is a cross-section of a corm showing 

interior lesions.

Rhizoctonia violaceae. Symptoms: Infections begin at the base of the corm, 

accompanied by reddish to dark violet mycelia.

Source: USDA-APHIS

Figure 2-42 Frost Damage on Gladiolus

Source: PPO

Figure 2-43 Kirkstip on Gladiolus
Corms

Gladiolus

2-40 Bulb Identification Manual 10/2011-01

Septoria gladioli. Symptoms: Water-soaked reddish brown to brownish black 

lesions becoming irregular, depressed, and black with definite margins but not 

penetrating the corm flesh. Many small lesions may coalesce into larger 

lesions. There may be tiny black sclerotia on the tunic, but normally the tunic 

must be removed to see the symptoms. Corm frequently becomes mummified 

during storage. Symptoms are similar to those of Stromatinia gladioli.

Other Pests

Aphids. Symptoms: If infestations are fresh, the corms may be sticky; live 

insects must be found.

Source: BKD

Figure 2-44 Rhizoctonia violaceae on Gladiolus

Source: nVWA

Figure 2-45 Septoria gladioli on Gladiolus
Corms

Gladiolus

10/2011-01 Bulb Identification Manual 2-41

No photo available.

Ditylenchus destructor. Symptoms: Extended brown streaks radiating from the 

base. The top photo below shows the apex and base of the corm. Note dark 

streaking radiating from the basal plate. The bottom photo shows a crosssection of the corm.

Meloidogyne. Symptoms: Swellings around the basal plate. Arrows in the photo 

below point to the characteristic abnormal swellings.

Source: BKD

Figure 2-46 Ditylenchus destructor on Gladiolus nanus
Corms

Gladiolus

2-42 Bulb Identification Manual 10/2011-01

Pseudomonas gladioli. Symptoms: Pale yellow, water-soaked circular lesions 

eventually becoming sunken and turning brown or nearly black and scab-like 

with a lacquered appearance.

Pseudomonas marginata. Symptoms: Dark, water-soaked lesions becoming dark 

brown, more or less circular and depressed and scab-like with elevated 

margins. Tunic often cracking longitudinally and developing oval to elongated 

dark brown spots. In the photo below, notice the characteristic scabs with 

raised margins.

Source: PPO

Figure 2-47 Meloidogyne on Gladiolus

Source: nVWA

Figure 2-48 Pseudomonas gladioli on Gladiolus
Corms

Gladiolus

10/2011-01 Bulb Identification Manual 2-43

Rhodococcus fascians. Symptoms: Small, thin, fan-like, fasciated scales at the 

base of the corm

Stromatinia gladioli. Symptoms: Small, hard, black sclerotia on the tunic. Brown 

to black, somewhat circular lesions on the corm surface, especially along the 

nodes, becoming sunken, often merging into large irregular areas and usually 

turning black with slightly raised margins. Decayed tissue is corky and corms 

often become mummified in storage.

Source: BKD

Figure 2-49 Pseudomonas marginata on Gladiolus

Source: PPO

Figure 2-50 Rhodococcus fascians on Gladiolus
Corms

Gladiolus

2-44 Bulb Identification Manual 10/2011-01

Urocystis gladiolicola. Symptoms: Yellowish welts on exterior of corm, exposing 

minute, raised, gray to black dots or black sori; with dark lesions on the 

interior. Dwarf varieties are particularly susceptible.

Source: USDA-APHIS

Figure 2-51 Stromatinia gladioli on Gladiolus
Corms

Gladiolus

10/2011-01 Bulb Identification Manual 2-45

Source: J. Heuperman

Figure 2-52 Urocystis gladiolicola on Gladiolus
Corms

Ixia

2-46 Bulb Identification Manual 10/2011-01

Ixia

Ixia corms are globose to teardrop-shaped, very irregular, and may be flattened 

at odd angles to the central axis. The tunic is medium-brown, with fine to 

moderately coarse netted fibers. A large lump of last year’s dried up corm may 

be present at the base of the corm. The central bud and sprouts are red. The 

interior of the corm is red or purple. This is the only corm with red to purple 

flesh.

Pest Risk Rating

The pest risk rating for Ixia is 3–4.

Similar Looking Corms

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select any abnormal corms for inspection.

Source: USDA-APHIS

Figure 2-53 Ixia
Corms

Ixia

10/2011-01 Bulb Identification Manual 2-47

3. Remove tunic, examine corm flesh and basal plate for disease symptoms.

Pests

Common Pests

None

Rare Pests

Fusarium oxysporum. Symptoms: Brown rot, usually beginning at the base of 

the corm.

No photo available.

Other Pests.

Sclerotium gladioli. symptoms: Dark corky lesions.

No photo available.
Corms

Sparaxis

2-48 Bulb Identification Manual 10/2011-01

Sparaxis

Sparaxis are globose to conical or ovoid corms, 0.75 inches (20 mm) tall. The 

tunic is shiny, white to cream-colored or dirty-white, and very fibrous with a 

woven, net-like appearance. There can be a spike-like stem and a flattened 

plate-like structure at the base of the corm. This plate is the remains of the 

roots produced during the growing season, and can easily be removed. The 

interior of the corm is white to cream in color. There are very few problems 

associated with Sparaxis.

Pest Risk Rating

The pest risk rating for Sparaxis is 3.

Similar Looking Corms

There are none.

Inspection Procedures

Source: USDA-APHIS

Figure 2-54 Sparaxis
Corms

Sparaxis

10/2011-01 Bulb Identification Manual 2-49

1. Check consignment and verify lot.

2. Look for soil contamination and select any abnormal corms for inspection.

3. Remove tunics and examine corm flesh and basal plate for disease 

symptoms.

Pests

Common Pests

None

Rare Pests

None

Other Pests

Aphids. Symptoms: No definite symptoms; live insects must be found.

No photo available.

Pseudomonas marginata. Symptoms: Dark, water-soaked lesions, becoming 

dark brown and more or less circular, depressed and scab-like with elevated 

margins. Tunic often cracking longitudinally and developing oval to elongated 

dark brown spots. 

No photo available.
Corms

Sparaxis

2-50 Bulb Identification Manual 10/2011-01
10/2011-01 Bulb Identification Manual 3-1

Chapter

3

Perennials

Contents

Introduction 3-4

Identification Procedure 3-5

Aconitum 3-6

Pest Risk Rating 3-6

Similar Looking Perennials 3-6

Inspection Procedures 3-6

Pests 3-7

Treatment 3-9

Agapanthus 3-10

Pest Risk Rating 3-10

Similar Looking Perennials 3-10

Inspection Procedures 3-10

Pests 3-11

Anemone 3-12

Pest Risk Rating 3-12

Similar Looking Perennials 3-12

Inspection Procedures 3-12

Pests 3-13

Aquilegia 3-14

Pest Risk Rating 3-14

Similar Looking Perennials 3-14

Inspection Procedures 3-14

Pests 3-15

Aruncus 3-16

Pest Risk Rating 3-17

Similar Looking Perennials 3-17

Inspection Procedures 3-17

Pests 3-17

Astrantia 3-19

Pest Risk Rating 3-19

Similar Looking Perennials 3-20

Inspection Procedures 3-20

Pests 3-20

Campanula 3-21

Pest Risk Rating 3-21

Similar Looking Perennials 3-21

Inspection Procedures 3-21
Perennials

Contents

3-2 Bulb Identification Manual 10/2011-01

Pests 3-21

Dicentra 3-24

Pest Risk Rating 3-24

Similar Looking Perennials 3-24

Inspection Procedures 3-25

Pests 3-25

Echinacea 3-27

Pest Risk Rating 3-27

Similar Looking Perennials 3-27

Inspection Procedures 3-28

Pests 3-28

Epimedium 3-29

Pest Risk Rating 3-30

Similar Looking Perennials 3-30

Inspection Procedures 3-30

Pests 3-30

Eremurus 3-33

Pest Risk Rating 3-33

Similar Looking Perennials 3-33

Inspection Procedures 3-33

Pests 3-34

Eryngium 3-35

Pest Risk Rating 3-35

Similar Looking Perennials 3-35

Inspection Procedures 3-36

Pests 3-36

Geranium 3-37

Pest Risk Rating 3-37

Similar Looking Perennials 3-37

Inspection Procedures 3-37

Pests 3-38

Heuchera 3-41

Pest Risk Rating 3-41

Similar Looking Perennials 3-41

Inspection Procedures 3-41

Pests 3-41

Hosta 3-44

Pest Risk Rating 3-44

Similar Looking Perennials 3-44

Inspection Procedures 3-44

Pests 3-44

Incarvillea 3-48

Pest Risk Rating 3-48

Similar Looking Perennials 3-48

Inspection Procedures 3-48
Perennials

Contents

10/2011-01 Bulb Identification Manual 3-3

Pests 3-48

Liatris 3-51

Pest Risk Rating 3-51

Similar Looking Perennials 3-51

Inspection Procedures 3-51

Pests 3-51

Ligularia 3-54

Pest Risk Rating 3-54

Similar Looking Perennials 3-54

Inspection Procedures 3-54

Pests 3-54

Papaver 3-57

Pest Risk Rating 3-57

Similar Looking Perennials 3-57

Inspection Procedures 3-57

Pests 3-57

Phlox 3-61

Pest Risk Rating 3-61

Similar Looking Perennials 3-61

Inspection Procedures 3-61

Pests 3-61

Platycodon 3-66

Pest Risk Rating 3-66

Similar Looking Perennials 3-67

Inspection Procedures 3-67

Pests 3-67

Pulmonaria 3-69

Pest Risk Rating 3-69

Similar Looking Perennials 3-69

Inspection Procedures 3-69

Pests 3-70

Rudbeckia 3-71

Pest Risk Rating 3-72

Similar Looking Perennials 3-72

Inspection Procedures 3-72

Pests 3-72

Salvia 3-73

Pest Risk Rating 3-73

Similar Looking Perennials 3-73

Inspection Procedures 3-73

Pests 3-74

Tradescantia 3-75

Pest Risk Rating 3-75

Similar Looking Perennials 3-75

Inspection Procedures 3-75
Perennials

Introduction

3-4 Bulb Identification Manual 10/2011-01

Pests 3-76

Veronica 3-77

Pest Risk Rating 3-77

Similar Looking Perennials 3-77

Inspection Procedures 3-78

Pests 3-78

Introduction

This section includes some of the perennials included in the approved list of 

bulbs in the Preclearance Program.

Some of these perennials are actually tubers and tuberous roots, rhizomes, or 

corms. Look at the pictures of the perennials and select the picture and 

description that fits your specimen. Soil or growing media can be a problem, 

especially if the plants were started from “plugs” or “jiffy pots,” or if the roots 

are otherwise tightly bound. Weeds can also be tangled up in the roots. All 

weeds, no matter how cosmopolitan, are prohibited. In addition, be on the 

lookout for perennials that are breaking dormancy. Any green parts over 2 

inches, or any fully expanded leaves even if smaller than 2 inches, are 

prohibited. Soil, weeds, and root knot nematode (Meloidogyne) are the most 

common reasons for rejections for perennials. 

Figure 3-1 Sketch of a Common Perennial, Grass
Perennials

Introduction

10/2011-01 Bulb Identification Manual 3-5

The information in this chapter includes the pest risk rating for each bulb. The 

ratings are:

Identification Procedure

Determine the length of the perennial you are identifying. Compare it with the 

photographs in this chapter and select the description that fits your perennial. 

Each description includes inspection procedures and pests of concern.

Source: USDA-APHIS

Figure 3-2 Growing Media and Weeds in Perennials1 2

1 Left photo: Dicentra spectabilis with growing media trapped between roots. Note how tightly 

bound the roots are. 

2 Right photo: Veronica with weeds tangled in the roots.

Table 3-1 Pest Risk Ratings for Perennials

Pest Risk Rating

1–2 Very low risk. Verify the genus in the shipment. Inspect if time is available

3–4 Low risk. Inspect if time is available.

5–6 Moderate risk. Provide normal inspection.

7–8 High risk. Inspect thoroughly.

9–10 Very high risk. Inspect very thoroughly.
Perennials

Aconitum

3-6 Bulb Identification Manual 10/2011-01

Aconitum

Aconitum can have roots that are fibrous, tuberous, or rhizomatous. The most 

common ones in the Netherlands have a dark brown tuberous tap root with a 

number of thick secondary roots with long slender tips. The bud is broadly 

joined to the crown.

Pest Risk Rating

The pest risk rating for Aconitum is 5–6.

Similar Looking Perennials

Other tap-rooted perennials are similar, but Aconitum has characteristically 

long and slender root tips.

Inspection Procedures

1. Check consignment and verify lot.

2. Check for proof of hot water treatment.

Source: USDA-APHIS

Figure 3-3 Aconitum
Perennials

Aconitum

10/2011-01 Bulb Identification Manual 3-7

3. Look for soil contamination and select abnormal plants for inspection.

4. Inspect the leaf scales, buds, fleshy roots, and small fine roots, if present. 

Look for borers, fungal infections, and nematodes.

Pests

Common Pests

Meloidogyne hapla. Symptoms: Galls and swellings on slender ends of 

secondary roots and on rootlets.

Rare Pests

None

Other Pests

Aphelenchoides. Symptoms: Blackened leaf bases. Samples must be sent to the 

laboratory for confirmation.

Source: USDA-APHIS

Figure 3-4 Meloidogyne on Aconitum
Perennials

Aconitum

3-8 Bulb Identification Manual 10/2011-01

Sclerotium rolfsii var. Delphinii. Symptoms: White mycelia and black sclerotia. 

No photo available

Pratylenchus. Symptoms: Lesions on roots.

No photo available.

Storage Rot. Symptoms: Wet rot.

No photo available.

Verticillium albo-atrum. Symptoms: Discoloration of vascular bundles.

Source: PPO

Figure 3-5 Aphelenchoides on Aconitum1

1 Note blackened apices of the leaf bases.
Perennials

Aconitum

10/2011-01 Bulb Identification Manual 3-9

Treatment

Dutch export regulations require the following mandatory hot water treatment 

for Aconitum to control leaf nematodes (Aphelenchoides ritzemabosi):

In 1 hour, heat the perennial to 43.5 °C and hold for 1 hour. Then cool quickly 

in cold water treated with Thiram (TMTD).

Treatments are performed by growers and exporters under the supervision of 

nVWA, Naktuinbouw, or BKD.

Source: PPO

Figure 3-6 Verticillium on Aconitum
Perennials

Agapanthus

3-10 Bulb Identification Manual 10/2011-01

Agapanthus

Agapanthus plants have thick rhizomatous rootstocks with fleshy leaf bases 

and thick, spaghetti-like roots. The root crown is topped with a bud and long, 

fibrous remnants of old leaves and papery remnants of old flower stalks. Very 

few phytosanitary problems are associated with Agapanthus.

Pest Risk Rating

The pest risk rating for Agapanthus is 3.

Similar Looking Perennials

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

Source: USDA-APHIS

Figure 3-7 Agapanthus
Perennials

Agapanthus

10/2011-01 Bulb Identification Manual 3-11

3. Inspect the buds, dried remnants, fleshy roots, and small fine roots, if 

present. Look for borers and nematodes.

Pests

Common Pests

None

Rare Pests

None

Other Pests.

Meloidogyne hapla. Symptoms: Galls and swellings on roots.

No photo available.
Perennials

Anemone

3-12 Bulb Identification Manual 10/2011-01

Anemone

Anemone plants have root stocks usually consisting of congested, slender, 

spidery, dark brown to black rhizomes with wiry roots and numerous long, 

slender stems with persister fibrous leaf bases. Numerous small, vegetative 

buds and a few sprouts may occur along the roots and rhizomes. When just 

emerging, these buds can be mistaken for root galls of Meloidogyne.

Pest Risk Rating

The pest risk rating for Anemone is 6.

Similar Looking Perennials

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

Source: USDA-APHIS

Figure 3-8 Anemone japonica1

1 Right photo shows buds and stolons emerging from primary roots.
Perennials

Anemone

10/2011-01 Bulb Identification Manual 3-13

3. Inspect the root crown and rooting system.

Pests

Common Pests

Meloidogyne hapla. Symptoms: Galls and swellings on roots and abnormal root 

growth.

Rare Pests

None

Other Pests

None

Source: G. v. Grinsven

Figure 3-9 Meloidogyne hapla on Anemone 1

1 Note abnormally branched root system
Perennials

Aquilegia

3-14 Bulb Identification Manual 10/2011-01

Aquilegia

Aquilegia has a carrot-like taproot with few thick, long side roots.

Pest Risk Rating

The pest risk rating for Aquilegia is 4–5.

Similar Looking Perennials

Eryngium, Aconitum, and other tap-rooted perennials are similar to Aquilegia.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

Source: USDA-APHIS

Figure 3-10 Aquilegia
Perennials

Aquilegia

10/2011-01 Bulb Identification Manual 3-15

3. Inspect the fleshy roots, and small fine roots. Look for borers and 

nematodes.

Pests

Common Pests

None

Rare Pests

Meloidogyne hapla. Symptoms: Galls and swellings on roots.

No photo available.

Pratylenchus. Symptoms: Lesions on roots.

No photo available.

Other Pests

None
Perennials

Aruncus

3-16 Bulb Identification Manual 10/2011-01

Aruncus

Aruncus root crowns are usually compact, with dormant buds and strong 

primary roots with numerous fine secondary roots. Depending on species, the 

root crown can become woods and rhizomatous. Sometimes propagated by 

“plugs” and the dense tangle of roots may trap growing media.

Growing media is not allowed in the program, so consignments contaminated 

with media should be refused. Generally, no amount of washing will remove 

the trapped media. This is a common problem with perennials propagated in 

this manner.

Source: USDA-APHIS

Figure 3-11 Aruncus1 2

1 Top photo: Specimen on the left was propagated from a cutting and kept in a small pot or 

“plug” where roots became pot-bound, trapping growing media.

2 Bottom photo: Close-up of root ball with trapped growing media (peat).
Perennials

Aruncus

10/2011-01 Bulb Identification Manual 3-17

Pest Risk Rating

The pest risk rating for Aruncus is 6.

Similar Looking Perennials

Aruncus plants resemble many other fine-rooted perennials.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root system. Plants that have been grown in “plugs” or “jiffy 

pots” often have pot-bound roots that trap growing media. Also check for 

nematodes.

Pests

Common Pests

Meloidogyne hapla. Symptoms: Galls and swellings on roots. The galls often 

cause a proliferation of abnormal, slender roots.

Source: USDA-APHIS

Figure 3-12 Meloidogyne hapla on Aruncus
Perennials

Aruncus

3-18 Bulb Identification Manual 10/2011-01

Rare Pests

None

Other Pests

None

Source: USDA-APHIS

Figure 3-13 Meloidogyne hapla on Aruncus
Perennials

Astrantia

10/2011-01 Bulb Identification Manual 3-19

Astrantia

Astrantia has black, somewhat brittle roots and usually woody root crowns 

with persistent tan fibers of old leaves surrounding a prominent bud.

Pest Risk Rating

The pest risk rating for Astrantia is 6.

Source: USDA-APHIS

Figure 3-14 Astrantia major
Perennials

Astrantia

3-20 Bulb Identification Manual 10/2011-01

Similar Looking Perennials

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root system. Look for nematodes.

Pests

Common Pests

Meloidogyne hapla. Symptoms: Swellings and galls throughout the root system. 

Infected root tips may become swollen.

Rare Pests

None

Other Pests

None

Source: USDA-APHIS

Figure 3-15 Meloidogyne hapla on Astrantia
Perennials

Campanula

10/2011-01 Bulb Identification Manual 3-21

Campanula

Campanula plants have thick, succulent whitish to cream-colored roots and 

root crowns that are somewhat woody. Primary roots resemble short, fat 

spaghetti. Fibers of old roots may be present at the base of the crown.

Pest Risk Rating

The pest risk rating for Campanula is 5.

Similar Looking Perennials

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root system. The dense roots may trap soil or growing media. 

Look for fungal infections and nematodes.

Pests

Source: USDA-APHIS

Figure 3-16 Campanula
Perennials

Campanula

3-22 Bulb Identification Manual 10/2011-01

Common Pests

Meloidogyne hapla. Symptoms: Proliferation of very small roots with small 

knobby swellings or galls.

Rare Pests

None

Other Pests

Pratylenchus. Symptoms: Lesions on roots.

No photo available.

Rhodococcus fascians. Symptoms: Fasciations at root crown.

Source: USDA-APHIS

Figure 3-17 Meloidogyne on Campanula lactiflora ‘Pouffe’1

1 Note proliferation of very small roots with small knots.
Perennials

Campanula

10/2011-01 Bulb Identification Manual 3-23

Source: USDA-APHIS

Figure 3-18 Campanula lactiflora ‘Pouffe’ with Rhodococcus fascians1

1 This specimen is also heavily infected with Meloidogyne.
Perennials

Dicentra

3-24 Bulb Identification Manual 10/2011-01

Dicentra

Two species are exported through the preclearance program. Dicentra 

spectabilis has a woody rootstock and stem and white or yellowish, stout, 

fleshy roots that are brittle and bruise easily. A few fine roots may be attached 

to the fleshy roots. Dicentra formosa, on the other hand, has numerous finer, 

spaghetti-like roots and prominent buds with persistent pinkish or green leaf 

bases. Both species are commonly found with growing media trapped within 

the root systems.

Pest Risk Rating

The pest risk rating for Dicentra is 6–7.

Similar Looking Perennials

Dicentra spectabilis is quite distinct, but D. formosa may resemble other 

perennials with prominent buds and a dense root system.

Source: USDA-APHIS

Figure 3-19 Dicentra spectabilis (left); Dicentra formosa (right)
Perennials

Dicentra

10/2011-01 Bulb Identification Manual 3-25

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination; common to both species.

3. Select abnormal plants for inspection.

Pests

Common Pests

None

Rare Pests

Penicillium. Symptoms: Blue-green mold, usually the result of poor storage 

conditions.

Storage Rot. Symptoms: Soft brown rot affecting the entire plant.

Source: USDA-APHIS

Figure 3-20 Penicillium on Dicentra stabilis
Perennials

Dicentra

3-26 Bulb Identification Manual 10/2011-01

Other Pests

Meloidogyne hapla. Symptoms: Swellings and galls on smaller roots.

No photo available.

Source: USDA-APHIS

Figure 3-21 Dicentra formosa with Storage Rot1

1 Sample on the left is healthy; samples on the right are affected with storage rot.
Perennials

Echinacea

10/2011-01 Bulb Identification Manual 3-27

Echinacea

Echinacea plants usually have a woody root crown often with several 

elongated buds and fibrous, cream-colored roots.

Pest Risk Rating

The pest risk rating for Echinacea is 6.

Similar Looking Perennials

Echinacea resembles other perennials with prominent buds at the root crown 

and cream-colored, fibrous roots.

Source: USDA-APHIS

Figure 3-22 Echinacea ‘Sunrise’
Perennials

Echinacea

3-28 Bulb Identification Manual 10/2011-01

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown and roots. Look for nematodes. The dense tangle of 

roots just below the root crown may trap growing media.

Pests

Common Pests

None

Rare Pests

Meloidogyne. Symptoms: Swellings and galls throughout the root system.

No photo available.

Rhodococcus. Symptoms: Fasciations at root crown.

Other Pests

None

Source: USDA-APHIS

Figure 3-23 Rhodococcus on Echinacea ‘Mango Meadowbrite’
Perennials

Epimedium

10/2011-01 Bulb Identification Manual 3-29

Epimedium

Epimedium plants are characterized by mats of fibrous, kinky, brittle roots 

attached to knobby, reddish-brown rhizomes. The rhizomes on some varieties 

resemble small, knobby, multi-branched sticks. Other varieties have root 

crowns with pinkish apical buds. Remnants of the previous years’ 

inflorescences are often present. Epimedium is one of the few perennials that is 

not affected by Meloidogyne.

Source: USDA-APHIS

Figure 3-24 Epimedium perralchium cv. Frohn Leitneri
Perennials

Epimedium

3-30 Bulb Identification Manual 10/2011-01

Pest Risk Rating

The pest risk rating for Epimedium is 6.

Similar Looking Perennials

Other fibrous-rooted perennials are similar to Epimedium.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown and small roots. The dense mass of fine roots in 

some varieties can trap growing media. Look for nematodes.

Pests

Common Pests

None

Rare Pests

Pratylenchus penetrans. Symptoms: Small, subtle warts on roots, especially a 

the tips. Samples must be sent to the laboratory for confirmation.

Source: USDA-APHIS

Figure 3-25 Epimedium youngianum
Perennials

Epimedium

10/2011-01 Bulb Identification Manual 3-31

Source: USDA-APHIS

Figure 3-26 Epimedium with Pratylenchus penetrans
Perennials

Epimedium

3-32 Bulb Identification Manual 10/2011-01

Other Pests

None

Source: USDA-APHIS

Figure 3-27 Epimedium youngianum with Pratylenchus penetrans1

1 Photo shows close-up of characteristic warts at root tips.
Perennials

Eremurus

10/2011-01 Bulb Identification Manual 3-33

Eremurus

Eremurus is very distinctive. It has a stout root crown with a prominent central 

bud surrounded by long, persistent fibers and thick fleshy roots that may be up 

to 6 inches (15 cm) or more in length, causing it to resemble an octopus. The 

bud is covered with tightly fitting papery skin and may be accompanied by a 

stump from last year’s flower stalk.

Pest Risk Rating

The pest risk rating for Eremurus is 3–4.

Similar Looking Perennials

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

Source: USDA-APHIS

Figure 3-28 Eremurus
Perennials

Eremurus

3-34 Bulb Identification Manual 10/2011-01

3. Cut apex of bud scale. A brown ring indicates the presence of 

Aphelenchoides.

Pests

Common Pests

None

Rare Pests

Storage Rot. Symptoms: Soft wet rot and discoloration of the central core.

Other Pests

Aphelenchoides ritsema-bosi. Symptoms: Brown discoloration of leaf scale, 

indicated by a brown ring.

No photo available.

Pratylenchus. Symptoms: Reddish or dark brown lesions on roots.

No photo available.

Source: USDA-APHIS

Figure 3-29 Storage Rot on Eremurus
Perennials

Eryngium

10/2011-01 Bulb Identification Manual 3-35

Eryngium

Eryngium plants have parsnip-like tap roots with thick side roots and smaller 

tertiary roots. Persistent fibers are often present at the root crown. There are 

very few problems with Eryngium.

Pest Risk Rating

The pest risk rating for Eryngium is 3–4.

Similar Looking Perennials

Aquilegia is similar.

Source: USDA-APHIS

Figure 3-30 Eryngium
Perennials

Eryngium

3-36 Bulb Identification Manual 10/2011-01

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the buds and roots. Look for nematodes and bacterial and fungal 

infections.

Pests

Common Pests

None

Rare Pests

Meloidogyne hapla. Symptoms: Swellings and galls on secondary roots.

Other Pests

Pratylenchus. Symptoms: Lesions on roots.

No photo available.

Source: USDA-APHIS

Figure 3-31 Meloidogyne on Eryngium alpinum
Perennials

Geranium

10/2011-01 Bulb Identification Manual 3-37

Geranium

Geranium plants vary considerably. Some have knobby, twig-like pink to 

reddish-brown rhizomatous, stoloniferous, or tuberous roots with relatively 

few smaller roots, while others have an abundance of fibrous roots. There are 

usually numerous buds and fibrous remains of old leaves at the root crown. 

Some varieties are propagated in plugs resulting in a dense tangle of roots that 

may trap growing media. The most common causes for rejection in Geranium

are soil (growing media) and Meloidogyne. Occasionally, the plants may have 

fully expanded leaves when presented for inspection. These lots should be 

rejected and reconditioned.

Pest Risk Rating

The pest risk rating for Geranium is 7–8.

Similar Looking Perennials

Other fibrous-rooted perennials are similar to Geranium.

Inspection Procedures

Source: USDA-APHIS

Figure 3-32 Two Types of Geranium
Perennials

Geranium

3-38 Bulb Identification Manual 10/2011-01

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown and smaller roots. The thick masses of roots in some 

varieties can trap soil or growing media. Look for nematodes, fungal, and 

bacterial infections.

Pests

Common Pests

Meloidogyne. Symptoms: Swellings and galls throughout the root system. Galls 

are often accompanied by an abnormal proliferation of small lateral roots.

Rare Pests

Rhodococcus fascians. Symptoms: Fasciations at the root crown.

Source: USDA-APHIS

Figure 3-33 Meloidogyne on Three Different Varieties of Geranium1

1 Swellings are much more numerous on the center specimen in the photo.
Perennials

Geranium

10/2011-01 Bulb Identification Manual 3-39

In some species, Rhodococcus-like galling may occur along the rhizomes. 

These proliferations of sprouts may or may not be caused by infections of 

Rhodococcus. Samples must be sent to the laboratory for identification.

Source: USDA-APHIS

Figure 3-34 Rhodococcus on Geranium1

1 Center specimen is severely infected. Specimen on the right is healthy. Fibers hide the fasciations on the specimen on the left.
Perennials

Geranium

3-40 Bulb Identification Manual 10/2011-01

Other Pests

Phytophthora cinnamomi. Symptoms: Brown to black wet rot.

No photo available.

Pratylenchus. Symptoms: Lesions on roots.

No photo available.

Source: USDA-APHIS

Figure 3-35 Geranium sanguineum with Anomalous Galling on Rhizomatous 

Roots
Perennials

Heuchera

10/2011-01 Bulb Identification Manual 3-41

Heuchera

Heuchera are compact plants with stout basal stems, persistent pink leaf bases 

and a strong root system. Heuchera is another plant that can be propagated in 

“plugs” or “jiffy pots.” The most common causes for rejections in Heuchera

are soil (growing media) and Meloidogyne.

Pest Risk Rating

The pest risk rating for Heuchera is 6–7.

Similar Looking Perennials

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown and root system. If the roots are densely tangled just 

below the root crown, inspect for trapped growing media. Look for 

nematodes and bacterial infections.

Pests

Source: USDA-APHIS

Figure 3-36 Heuchera
Perennials

Heuchera

3-42 Bulb Identification Manual 10/2011-01

Common Pests

Meloidogyne hapla. Symptoms: Swellings and galls on roots. Galls are 

frequently accompanied by a proliferation of very small rootlets.

Source: USDA-APHIS

Figure 3-37 Heuchera ‘Plum Pudding’ with Meloidogyne hapla1

1 Left photo: Note proliferation of very small roots with root knots just below the root crown. 

Right photo: Close-up of root mass with abundance of root knots.
Perennials

Heuchera

10/2011-01 Bulb Identification Manual 3-43

Rare Pests

None

Other Pests

Pratylenchus. Symptoms: Lesions on roots.

No photo available.

Rhodococcus fascians. Symptoms: Fasciations at the root crown.

No photo available.

Source: USDA-APHIS

Figure 3-38 Close-up of Swellings Caused by Meloidogyne hapla and 

Proliferation of Abnormal, Fine Rootlets
Perennials

Hosta

3-44 Bulb Identification Manual 10/2011-01

Hosta

Hosta plants have spaghetti-like roots with numerous side roots. The crown 

has conical buds and fibers from old leaves. At one time, Meloidogyne was 

common in Hosta, but it is rarely seen now. Today, weeds and soil are the most 

common reasons for rejections.

Pest Risk Rating

The pest risk rating for Hosta is 6.

Similar Looking Perennials

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the buds and small fine roots. Look for nematodes and fungal 

infections.

Pests

Source: USDA-APHIS

Figure 3-39 Hosta
Perennials

Hosta

10/2011-01 Bulb Identification Manual 3-45

Common Pests

None

Rare Pests

Meloidogyne. Symptoms: Swellings and galls throughout the root system. 

Occasionally, there may be little or no gall formation, but the root tips may be 

infected, causing stunting, a proliferation of side roots and a bushy root system.

Storage Rot. Symptoms: Wet rot of the root crown and bud, spreading into the 

roots.

Source: G. v. Grinsven

Figure 3-40 Meloidogyne Infection Causing Swollen Root Tips and Densely 

Bushy Root System

Source: USDA-APHIS

Figure 3-41 Stunted Root Tips and Abnormal Root Growth Caused by 

Meloidogyne
Perennials

Hosta

3-46 Bulb Identification Manual 10/2011-01

Other Pests

Botrytis. Symptoms: White or grayish mold. This is a rare problem, normally 

due to improper storage.

Source: USDA-APHIS

Figure 3-42 Storage Rot on Hosta with Early Botrytis Infection on Roots and 

Apex
Perennials

Hosta

10/2011-01 Bulb Identification Manual 3-47

Pratylenchus. Symptoms: Dark, linear, necrotic lesions on roots, followed by 

general decay.

Source: USDA-APHIS

Figure 3-43 Botrytis Infection on Hosta Roots

Source: G. v. Grinsven

Figure 3-44 Pratylenchus penetrans on Hosta
Perennials

Incarvillea

3-48 Bulb Identification Manual 10/2011-01

Incarvillea

Incarvillea are 6–8 inches in length. The plant has a very distinctive shape 

characterized by a cluster of light brown, fleshy, brittle roots topped with a 

corky, thick stem. The stem has small side buds that resemble warts. The roots 

are dotted with knobby projections. Incarvillea are shipped in winter.

Pest Risk Rating

The pest risk rating for Incarvillea is 2–3.

Similar Looking Perennials

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown and fleshy roots. Look for fungal and bacterial 

infections.

Pests

Common Pests

None

Source: USDA-APHIS

Figure 3-45 Incarvillea
Perennials

Incarvillea

10/2011-01 Bulb Identification Manual 3-49

Rare Pests

Phytophthora cactorum. Symptoms: Dark brown to purplish discoloration and 

rotting mainly on the tuberous roots, but also at the stem.

Source: PPO

Figure 3-46 Phytophthora sp. on Incarvillea

Source: PPO

Figure 3-47 Phytophthora sp. on Incarvillea Showing Longitudinal Sections of 

Infected Roots
Perennials

Incarvillea

3-50 Bulb Identification Manual 10/2011-01

Other Pests

Agrobacterium tumefasciens. Symptoms: Smooth cankers, usually at the root 

crown.

No photo available.

Rhodococcus fascians. Symptoms: Fasciations, usually at the root crown.

No photo available.
Perennials

Liatris

10/2011-01 Bulb Identification Manual 3-51

Liatris

Liatris is a plump, knobby, dark brown corm. The crown has small blade-like 

buds and distinctive circular, undulating ridges that expand outward from the 

center. The base of the corm may have short, worm-like new roots and/or fine 

fibers of old roots.

Pest Risk Rating

The pest risk rating for Liatris is 5–6.

Similar Looking Perennials

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the corms and small fine roots, if present. Cut off small pieces of 

the corms and examine the vascular areas.

Pests

Source: USDA-APHIS

Figure 3-48 Liatris
Perennials

Liatris

3-52 Bulb Identification Manual 10/2011-01

Common Pests

None

Rare Pests

Verticillium. Symptoms: Dark brown discoloration of the vascular bundles.

Other Pests

Botrytis. Symptoms: Wet decay and gray mold.

Source: J. Heuperman

Figure 3-49 Verticillium on Liatris
Perennials

Liatris

10/2011-01 Bulb Identification Manual 3-53

Ditylenchus destructor (only L. calilepsis). Symptoms: Discoloration of core.

Source: BKD

Figure 3-50 Botrytis on Liatris with White/Gray Mycelium

Source: PPO

Figure 3-51 Ditylenchus destructor on Liatris calilepsis1

1 In the top left sample (cross section) the infection has not yet affected the core. In the samples on the right (longitudinal section) and bottom (cross section) the infection has already 

affected the core.
Perennials

Ligularia

3-54 Bulb Identification Manual 10/2011-01

Ligularia

Ligularia has a root crown with long persistent fibers of the old leaves and 

masses of long, thick spaghetti-like roots and few secondary roots. Remnants 

of the previous years’ stem may be present.

Pest Risk Rating

The pest risk rating for Ligularia is 5–6.

Similar Looking Perennials

Ligularia is similar to other perennials with long, spaghetti-like roots.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown, fleshy roots, and small fine roots, if present. Look 

for nematodes and fungal infections.

Pests

Source: USDA-APHIS

Figure 3-52 Ligularia
Perennials

Ligularia

10/2011-01 Bulb Identification Manual 3-55

Common Pests

Meloidogyne. Symptoms: Galls and swellings on smaller roots.

Rare Pests

None

Other Pests

Botrytis. Symptoms: Brown, wet rot of the root crown, and gray mold.

Source: USDA-APHIS

Figure 3-53 Meloidogyne on Ligularia

Source: USDA-APHIS

Figure 3-54 Meloidogyne on Ligularia
Perennials

Ligularia

3-56 Bulb Identification Manual 10/2011-01

Pratylenchus. Symptoms: Lesions on roots.

No photo available.

Source: USDA-APHIS

Figure 3-55 Early Stages of Botrytis Rot on Ligularia
Perennials

Papaver

10/2011-01 Bulb Identification Manual 3-57

Papaver

Papaver has a woody root crown or stem and long, brown, brittle tap roots 

with few thick, secondary roots. In older plants, the roots near the crown are 

woody. The crown area is distinct with a tuft of new growth and old debris.

Pest Risk Rating

The pest risk rating for Papaver is 4–5.

Similar Looking Perennials

Papaver is similar to other tap-rooted perennials.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown, fleshy roots, and small fine roots, if present.

Pests

Source: USDA-APHIS

Figure 3-56 Papaver
Perennials

Papaver

3-58 Bulb Identification Manual 10/2011-01

Common Pests

None

Rare Pests

Storage Rot. Symptoms: Wet rot usually affecting damaged areas and spreading 

through the root crown and into the roots. Caused by mechanical injury and 

poor storage conditions.

Other Pests

Agrobacterium tumefasciens. Symptoms: Smooth galls at root crown.

Source: USDA-APHIS

Figure 3-57 Storage Rot on Papaver1

1 Photo: Note unidentified secondary fungus on decaying tissue.
Perennials

Papaver

10/2011-01 Bulb Identification Manual 3-59

Meloidogyne. Symptoms: Galls and swellings on smaller roots.

Source: G. v. Grinsven

Figure 3-58 Agrobacterium tumefasciens on Papaver
Perennials

Papaver

3-60 Bulb Identification Manual 10/2011-01

Source: G. v. Grinsven

Figure 3-59 Meloidogyne hapla on Roots of Papaver
Perennials

Phlox

10/2011-01 Bulb Identification Manual 3-61

Phlox

Phlox is characterized by its strong stems and fibrous, whitish roots. This is 

another plant that can be propagated in plugs or jiffy pots.

Pest Risk Rating

The pest risk rating for Phlox is 6–7.

Similar Looking Perennials

Phlox resembles most other perennials with strong stems and fibrous roots.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown and small fine roots. If roots are tightly tangled, 

check for growing media. Look for nematodes and bacterial infections.

Pests

Source: USDA-APHIS

Figure 3-60 Phlox
Perennials

Phlox

3-62 Bulb Identification Manual 10/2011-01

Common Pests

None

Rare Pests

Meloidogyne. Symptoms: Galls and swellings on roots. Galls are frequently 

accompanied by a proliferation of small rootlets. Occasionally, mixed 

infections of Meloidogyne and Pratylenchus occur on the same plant. Samples 

must be sent to the laboratory for confirmation.

Source: USDA-APHIS

Figure 3-61 Meloidogyne on Phlox1

1 Symptoms are not always apparent. Note swellings associated with a profusion of small roots 

along primary roots.
Perennials

Phlox

10/2011-01 Bulb Identification Manual 3-63

Pratylenchus. Symptoms: Swellings on roots. Typical reddish lesions may or 

may not be present. Symptoms are similar to those of Meloidogyne or even 

Rhodococcus. Samples must be sent to the laboratory for confirmation.

Source: USDA-APHIS

Figure 3-62 Meloidogyne on Phlox1

1 Top photo: Subtle swellings along primary roots and associated rootlets. Bottom photo: More 

typical symptoms of Meloidogyne.
Perennials

Phlox

3-64 Bulb Identification Manual 10/2011-01

Rhodococcus fascians. Symptoms: Fasciations, usually at the root crown, but 

may also occur among the roots.

Source: USDA-APHIS

Figure 3-63 Pratylenchus penetrans on Phlox

Source: USDA-APHIS

Figure 3-64 Rhodococcus fascians on Phlox
Perennials

Phlox

10/2011-01 Bulb Identification Manual 3-65

Other Pests

None
Perennials

Platycodon

3-66 Bulb Identification Manual 10/2011-01

Platycodon

Platycodon is a plant with cream-colored or whitish carrot-like roots, about 6 

inches long, with numerous smaller roots. The thick roots are frequently 

branched and may resemble ginseng roots. The crown is sometimes topped 

with a few small pinkish buds. Platycodon is not susceptible to Meloidogyne.

Pest Risk Rating

The pest risk rating for Platycodon is 4–5.

Source: USDA-APHIS

Figure 3-65 Platycodon
Perennials

Platycodon

10/2011-01 Bulb Identification Manual 3-67

Similar Looking Perennials

Platycodon is similar to other tap-rooted perennials.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown and small fine roots, as well as the tap roots. 

Growing media may be trapped between thick succulent roots.

Pests

Common Pests

None

Rare Pests

None

Other Pests

Botrytis cineria. Symptoms: Brown wet decay and gray mold.

No photo available.

Storage Rot (Soft Rot). Symptoms: Soft, wet, progressive rot.
Perennials

Platycodon

3-68 Bulb Identification Manual 10/2011-01

Source: G. v. Grinsven

Figure 3-66 Storage Rot on Platycodon
Perennials

Pulmonaria

10/2011-01 Bulb Identification Manual 3-69

Pulmonaria

The rootstock of Pulmonaria is woody with few to numerous short upright 

stems with an apical and several axillary buds with pinkish sheaths. The 

primary roots are long and spaghetti-like and bear numerous fine secondary 

roots.

Pest Risk Rating

The pest risk rating for Pulmonaria is 5.

Similar Looking Perennials

Dicentra formosa is similar, but the rootstock is not as woody as that of 

Pulmonaria, and it lacks the abundance of secondary and tertiary roots. Salvia

is similar because it can also have numerous buds on the root crown. It is not

as woody as Pulmonaria and it has many more secondary and tertiary roots.

Inspection Procedures

1. Check consignment and verify lot.

Source: USDA-APHIS

Figure 3-67 Pulmonaria
Perennials

Pulmonaria

3-70 Bulb Identification Manual 10/2011-01

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the buds and roots. Look for nematodes, and bacterial and fungal 

infections.

Pests

Common Pests

None

Rare Pests

Meloidogyne hapla. Symptoms: Swellings and galls on roots.

Other Pests

Pratylenchus. Symptoms: Lesions on roots.

No photo available.

Source: USDA-APHIS

Figure 3-68 Meloidogyne on Pulmonaria
Perennials

Rudbeckia

10/2011-01 Bulb Identification Manual 3-71

Rudbeckia

Rudbeckia plants have woody rootstocks and strong, almost woody stems. The 

primary roots are whitish to tan in color, straight, and bear very few secondary 

roots.

Source: USDA-APHIS

Figure 3-69 Rudbeckia
Perennials

Rudbeckia

3-72 Bulb Identification Manual 10/2011-01

Pest Risk Rating

The pest risk rating for Rudbeckia is 4.

Similar Looking Perennials

Tradescantia is similar, but not as woody as Rudbeckia.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the buds and roots. Look for nematodes, and bacterial and fungal 

infections.

Pests

Common Pests

None

Rare Pests

Meloidogyne hapla. Symptoms: Swellings and galls on roots.

No photo available.

Other Pests

Pratylenchus. Symptoms: Lesions on roots.

No photo available.
Perennials

Salvia

10/2011-01 Bulb Identification Manual 3-73

Salvia

Salvia plants have a root crown with many pinkish buds and often with 

remnants of the old stems. The root system can be dense with numerous fine 

secondary and tertiary roots. Some species have rhizomatous or tuberous 

rootstocks. Salvia is sometimes propagated in plugs or jiffy pots.

Pest Risk Rating

The pest risk rating for Salvia is 6–7.

Similar Looking Perennials

Pulmonaria is similar, but the rootstock is much woodier than that of Salvia. 

Salvia has many more secondary and tertiary roots than Pulmonaria.

Inspection Procedures

1. Check consignment and verify lot.

Source: USDA-APHIS

Figure 3-70 Salvia nemorosa ‘Sensation’ (left); Salvia pratensis ‘Madeline’ 

(right)
Perennials

Salvia

3-74 Bulb Identification Manual 10/2011-01

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown and small roots. If roots are tightly tangled, check 

for growing media. Look for nematodes.

Pests

Common Pests

None

Rare Pests

Meloidogyne. Symptoms: Galls and swellings on smaller roots.

No photo available.

Other Pests

Pratylenchus. Symptoms: Lesions on roots.

No photo available.
Perennials

Tradescantia

10/2011-01 Bulb Identification Manual 3-75

Tradescantia

Tradescantia rhizomes are jointed, resembling small bamboo. The roots are 

spaghetti-like with very few smaller roots. The buds are pointed and slender. 

Tradescantia is not affected by Meloidogyne.

Pest Risk Rating

The pest risk rating for Tradescantia is 3–4.

Similar Looking Perennials

Rudbeckia is similar, but more woody.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown and roots. Look for nematodes.

Source: USDA-APHIS

Figure 3-71 Tradescantia
Perennials

Tradescantia

3-76 Bulb Identification Manual 10/2011-01

Pests

Common Pests

None

Rare Pests

None

Other Pests

Frost Damage: Symptoms: 

No photo available.

Pratylenchus. Symptoms: Lesions on roots.

No photo available.
Perennials

Veronica

10/2011-01 Bulb Identification Manual 3-77

Veronica

Veronica plants have strong, nearly woody root crowns, strong upright stems, 

prominent buds, and a fibrous root system with long primary roots and an 

abundance of secondary roots.

Pest Risk Rating

The pest risk rating for Veronica is 6–7.

Similar Looking Perennials

Rudbeckia is similar, but more woody, and the primary roots have fewer 

secondary roots.

Source: USDA-APHIS

Figure 3-72 Veronica
Perennials

Veronica

3-78 Bulb Identification Manual 10/2011-01

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal plants for inspection.

3. Inspect the root crown and roots. Look for nematodes.

Pests

Common Pests

Meloidogyne. Symptoms: Galls and swellings on roots. The galls are often 

accompanied by a proliferation of small lateral roots.

Rare Pests

Rhodococcus. Symptoms: Fasciations at root crown and among roots.

Source: USDA-APHIS

Figure 3-73 Meloidogyne on Veronica
Perennials

Veronica

10/2011-01 Bulb Identification Manual 3-79

Other Pests

Frost Damage. Symptoms:

No photo available.

Pratylenchus. Symptoms: Lesions on roots.

No photo available.

Source: USDA-APHIS

Figure 3-74 Rhodococcus fascians on Veronica
Perennials

Veronica

3-80 Bulb Identification Manual 10/2011-01
10/2011-01 Bulb Identification Manual 4-1

Chapter

4

Rhizomes

Contents

Introduction 4-2

Identification Procedure 4-2

Astilbe 4-3

Pest Risk Rating 4-3

Similar Looking Rhizomes 4-3

Inspection Procedures 4-3

Pests 4-4

Treatment 4-4

Canna 4-6

Pest Risk Rating 4-6

Similar Looking Rhizomes 4-6

Inspection Procedures 4-6

Pests 4-7

Convallaria 4-8

Pest Risk Rating 4-8

Similar Looking Rhizomes 4-8

Inspection Procedures 4-8

Pests 4-8

Hemerocallis 4-10

Pest Risk Rating 4-10

Similar Looking Rhizomes 4-10

Inspection Procedures 4-10

Pests 4-11

Iris (mostly Iris germanica, I. pseudacorus, I. siberica, and I. ensata) 4-12

Pest Risk Rating 4-12

Similar Looking Rhizomes 4-12

Inspection Procedures 4-12

Pests 4-12

Paeonia 4-14

Pest Risk Rating 4-14

Similar Looking Rhizomes 4-14

Inspection Procedures 4-14

Pests 4-14

Treatment 4-17

Zantedeschia 4-18

Pest Risk Rating 4-18

Similar Looking Rhizomes 4-18
Rhizomes

Introduction

4-2 Bulb Identification Manual 10/2011-01

Inspection Procedures 4-19

Pests 4-19

Introduction

Rhizomes are swollen horizontal stems that grow along or below the surface of 

the ground. They have nodes and internodes and the tips of the stems have 

large buds, often covered with scale-like leaves. When rhizomes grow, the 

terminal buds expand and produce new horizontal stems.

The information in this chapter includes the pest risk rating for each bulb. The 

ratings are:

Identification Procedure

Determine the length of the rhizome you are identifying. Compare it with the 

photographs in this chapter and select the description that fits your rhizome. 

Each description includes inspection procedures and pests of concern.

Figure 4-1 Iris Rhizome Sketch 

Table 4-1 Pest Risk Ratings for Rhizomes

Pest Risk Rating

1–2 Very low risk. Verify the genus in the shipment. Inspect if time is available.

3–4 Low risk. Inspect if time is available.

5–6 Moderate risk. Provide normal inspection.

7–8 High risk. Inspect thoroughly.

9–10 Very high risk. Inspect very thoroughly.
Rhizomes

Astilbe

10/2011-01 Bulb Identification Manual 4-3

Astilbe

Astilbe rhizomes are woody and are usually covered with black or dark brown 

wool and dense mats of fibrous black or brown roots. Buds are covered with 

reddish-brown wool. If they have gone through the required hot water 

treatment recently, the wool on they buds will be black. If the plants have had 

time to grow after treatment, the buds will be reddish. Soil, growing media or 

weeds may be trapped in the dense mat of roots.

Pest Risk Rating

The pest risk rating for Astilbe is 7.

Similar Looking Rhizomes

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Check for a paper with a Dutch stamp indicating that hot water treatment 

was done.

3. If such a document is not present, REFUSE TO INSPECT.

Source: USDA-APHIS

Figure 4-2 Astilbe
Rhizomes

Astilbe

4-4 Bulb Identification Manual 10/2011-01

4. Look for soil contamination by breaking apart the root mass.

5. Select abnormal specimens for inspection.

6. Check roots for nematodes.

Pests

Common Pests

Meloidogyne. Symptoms: Swellings and galls on roots.

Rare Pests

None

Other Pests

None

Treatment

Dutch export regulations require the following mandatory hot water treatment 

for Astilbe to control leaf nematodes (Aphelenchoides ritzemabosi):

In 1 hour, heat the rhizome to 43.5 C and hold for 1 hour. Then cool quickly in 

cold water treated with Thiram (TMTD).

Source: USDA-APHIS

Figure 4-3 Meloidogyne on Astilbe
Rhizomes

Astilbe

10/2011-01 Bulb Identification Manual 4-5

Treatments are performed by growers and exporters under the supervision of 

nVWA, Naktuinbouw or BKD.
Rhizomes

Canna

4-6 Bulb Identification Manual 10/2011-01

Canna

Canna rhizomes are branched, fleshy, stout, 1–1.5 inches (25–38 mm) thick 

and 3–4 inches (76–102 mm) long, and have distinct nodes with the remains of 

papery leaf bases. There is a large bud on the tip of each branch, and roots may 

be attached anywhere along the rhizome. The bud is often sheathed by the 

basal remnants of the previous year’s leaf.

Pest Risk Rating

The pest risk rating for Canna is 3.

Similar Looking Rhizomes

Rhizomes of Iris germanica are similar but are more flattened and roots come 

directly from the bottom of the rhizome.

Inspection Procedures

1. Check small roots for nematodes.

2. Look at brown, necrotic buds for Ditylanchus destructor.

3. Look for soil contamination, especially under the leaf sheaths.

Source: USDA-APHIS

Figure 4-4 Canna
Rhizomes

Canna

10/2011-01 Bulb Identification Manual 4-7

Pests

Common Pests

None

Rare Pests

Botrytis cineria. Symptoms: Soft, water-soaked areas becoming tan-colored 

when dry.

Other Pests

Ditylenchus destructor. Symptoms: Brown, necrotic buds.

No photo available.

Meloidogyne. Symptoms: Galls and swellings on small roots.

No photo available.

Source: PPO

Figure 4-5 Botrytis cineria on Canna
Rhizomes

Convallaria

4-8 Bulb Identification Manual 10/2011-01

Convallaria

The rootstock of Convallaria is a horizontal rhizome with conspicuous buds 

(pips) and long fibrous roots. The buds are occasionally connected to each 

other by stolons. Convallaria are shipped during the winter.

Pest Risk Rating

The pest risk rating for Convallaria is 5.

Similar Looking Rhizomes

There are none.

Inspection Procedures

1. Look for soil and weeds.

2. Look for red lesions on roots.

Pests

Common Pests

None

Source: USDA-APHIS

Figure 4-6 Convallaria majalis
Rhizomes

Convallaria

10/2011-01 Bulb Identification Manual 4-9

Rare Pests

Pratylenchus. Symptoms: Red lesions, becoming dark brown to black, on roots 

and rhizomes. Heavy infestations will result in secondary rotting.

Other Pests

None

Source: G. v. Grinsven

Figure 4-7 Convallaria with Pratylenchus convallariae
Rhizomes

Hemerocallis

4-10 Bulb Identification Manual 10/2011-01

Hemerocallis

Hemerocallis has short rhizomes with leafy buds or eyes and thick, succulent, 

yellowish-brown roots, often with tuber-like swellings. The fibrous remains of 

old leaves may be seen at the base of the buds. Hemerocallis is shipped in the 

winter.

Pest Risk Rating

The pest risk rating for Hemerocallis is 2–3.

Similar Looking Rhizomes

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Make sure leaf bases are no more than 2 inches long.

3. Look for soil contamination.

Source: USDA-APHIS

Figure 4-8 Hemerocallis
Rhizomes

Hemerocallis

10/2011-01 Bulb Identification Manual 4-11

4. Select specimens for inspection, especially those that look different from 

the rest.

5. Examine buds and roots for evidence of borers, diseases, and nematodes.

Pests

Common Pests

None

Rare Pests

Meloidogyne hapla. Symptoms: Galls and swellings on roots.

No photo available.

Pratylenchus. Symptoms: Dark depressed lesions on roots.

Other Pests

None

Source: G. v. Grinsven

Figure 4-9 Pratylenchus penetrans on Hemerocallis
Rhizomes

Iris (mostly Iris germanica, I. pseudacorus, I. siberica, and I. ensata)

4-12 Bulb Identification Manual 10/2011-01

Iris (mostly Iris germanica, I. pseudacorus, I. siberica, and I. ensata)

Iris rhizomes can be short and stout and somewhat flattened, up to 1.5 inches 

(38 mm) in diameter and up to 3–4 inches (76–102 mm) long, slender, and very 

short or long, slender and stoloniferous. They are usually horizontal and 

clump-forming, but in some species they are vertically oriented. Nodes may be 

indistinct, and fibrous or papery remains of old leaves may be present near the 

buds. The buds are leafy with no papery covering. The roots are often wiry. In 

Iris germanica and its cultivars, the roots are attached to the bottom of the 

rhizome and do not break off easily.

Pest Risk Rating

Iris has a pest risk rating of 3–4.

Similar Looking Rhizomes

Canna rhizomes resemble those of Iris germanica. Remains of leaves may be 

present on most of the Canna rhizome. Leaf remnants on Iris occur only near 

the buds.

Inspection Procedures

1. Look for soil.

2. Smell for bacterial soft rot, Erwinia. The rhizome will have a bad odor if 

rot is present. It is very rare and only occurs in Iris germanica.

3. Look for nematodes on roots.

Pests

Source: USDA-APHIS

Figure 4-10 Iris germanica (left), Iris siberica (right) 
Rhizomes

Iris (mostly Iris germanica, I. pseudacorus, I. siberica, and I. ensata)

10/2011-01 Bulb Identification Manual 4-13

Common Pests

None

Rare Pests

Pratylenchus. Symptoms: Reddish to brown lesions on roots, followed by 

general decay.

Other Pests

None

Source: G. v. Grinsven

Figure 4-11 Pratylenchus penetrans on Iris1

1 Left photo: Iris ensata. Right photo: Iris setosa.
Rhizomes

Paeonia

4-14 Bulb Identification Manual 10/2011-01

Paeonia

Paeonia has woody, flesh-colored to dark brown or blackish rhizomes and 

thick tuberous roots with a few or no fibrous roots.

Pest Risk Rating

The pest risk rating for Paeonia is 5–6.

Similar Looking Rhizomes

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Check for proof of hot water treatment.

3. Look for soil contamination and select abnormal plants for inspection.

Pests

Common Pests

Meloidogyne. Symptoms: Swellings and galls, mostly on secondary roots.

Source: USDA-APHIS

Figure 4-12 Two Varieties of Paeonia
Rhizomes

Paeonia

10/2011-01 Bulb Identification Manual 4-15

Source: USDA-APHIS

Figure 4-13 Meloidogyne on Paeonia1 2

1 Left photo: typical symptoms of Meloidogyne. 

2 Right photo: examples of swellings that are not Meloidogyne. Note that these swellings are 

irregular in shape and sometimes off to one side of the rootlet. Such features are common 

on some varieties of P. officianalis (“farmer’s peonies”).

Source: USDA-APHIS

Figure 4-14 Swellings on Paeonia Roots1
Rhizomes

Paeonia

4-16 Bulb Identification Manual 10/2011-01

Rare Pests

Penicillium. Symptoms: Blue-green mold. This is normally only a storage 

problem.

Other Pests

Botrytis paeoniae. Symptoms: Black sclerotia imbedded in old stems.

No photo available.

Rhodococcus fascians. Symptoms: Fasciations at root crown.

1 Example of large swellings on the roots of some varieties of Paeonia. These tuber-like swellings are not symptoms of Meloidogyne.

Source: USDA-APHIS

Figure 4-15 Penicillium on Paeonia
Rhizomes

Paeonia

10/2011-01 Bulb Identification Manual 4-17

Treatment

Dutch export regulations require the following mandatory hot water treatment 

for Paeonia to control leaf nematodes (Aphelenchoides ritzemabosi):

In 1 hour, heat the rhizome to 43.5 C and hold for 1 hour. Then cool quickly in 

cold water treated with Thiram (TMTD).

Treatments are performed by growers and exporters under the supervision of 

nVWA, Naktuinbouw or BKD.

Source: G. v. Grinsven

Figure 4-16 Paeonia with Rhodococcus fascians
Rhizomes

Zantedeschia

4-18 Bulb Identification Manual 10/2011-01

Zantedeschia

The genus Zantedeschia consists of eight species over two sections, 

Zantedeschia and Aestivae. Zantedeschia has rhizomes, rhizomatous tubers or 

discoid tubers. Zantedeschia aethiopica and other species in Section 

Zantedeschia have rhizomatous tubers that are more or less elongate. Species 

in Section Aestivae such as Z. rehmannii, Z. elliotiana, and Z. albomaculata

and their hybrids have discoid tubers with up to seven knobby daughter 

“bulblets.” The major problem for Zantedeschia is soil.

Pest Risk Rating

The pest risk rating for Zantedeschia is 3.

Similar Looking Rhizomes

Arum (tuber) may or may not have side “bulblets.”

Source: USDA-APHIS

Figure 4-17 Zantedeschia1 2

1 Top left and right photos show examples of discoid tubers of Zantedeschia Section Astivae. 

2 Bottom left photo is a rhizomatous tuber of Zantedeschia aethiopica.
Rhizomes

Zantedeschia

10/2011-01 Bulb Identification Manual 4-19

Inspection Procedures

1. Select abnormal rhizomes for inspection.

2. Check for softness.

3. Check for soil.

Pests

Common Pests

None

Rare Pests

Erwinia carotovora. Symptoms: Soft brown rot with fetid odor. Species in 

Section Aestivae are more susceptible to Erwinia than those in Section 

Zantedeschia. Erwinia is normally culled out by the exporter before the 

preclearance inspections and is rarely intercepted.

Other Pests

Rhizoglyphus. Symptoms: A secondary pest in decaying tissue.

No photo available.

Source: USDA-APHIS

Figure 4-18 Erwinia carotovora on Zantedeschia1

1 Two examples of Erwinia carotovora on Zantedeschia. Left photo shows fresh infection with 

mushy tissue. Right photo shows old infection with brown, dried tissue.
Rhizomes

Zantedeschia

4-20 Bulb Identification Manual 10/2011-01
10/2011-01 Bulb Identification Manual 5-1

Chapter

5

True Bulbs

Contents

Introduction 5-3

Identification Procedure 5-5

Allium (flowering onion) 5-6

Pest Risk Rating 5-6

Similar Looking Bulbs 5-7

Inspection Procedures 5-7

Pests 5-7

Camassia 5-13

Pest Risk Rating 5-13

Similar Looking Bulbs 5-13

Inspection Procedures 5-13

Pests 5-14

Chionodoxa 5-15

Pest Risk Rating 5-15

Similar Looking Bulbs 5-15

Inspection Procedures 5-15

Pests 5-15

Fritillaria 5-18

Pest Risk Rating 5-19

Similar Looking Bulbs 5-19

Inspection Procedures 5-19

Pests 5-19

Galanthus 5-22

Pest Risk Rating 5-22

Similar Looking Bulbs 5-22

Inspection Procedures 5-22

Pests 5-23

Galtonia 5-25

Pest Risk Rating 5-25

Similar Looking Bulbs 5-25

Inspection Procedures 5-25

Pests 5-26

Hippeastrum 5-27

Pest Risk Rating 5-27

Similar Looking Bulbs 5-27

Inspection Procedures 5-27

Pests 5-28
True Bulbs

Contents

5-2 Bulb Identification Manual 10/2011-01

Hyacinthus 5-32

Pest Risk Rating 5-32

Similar Looking Bulbs 5-32

Inspection Procedures 5-32

Pests 5-33

Iris 5-40

Pest Risk Rating 5-40

Similar Looking Bulbs 5-40

Inspection Procedures 5-40

Pests 5-41

Lilium 5-47

Pest Risk Rating 5-47

Similar Looking Bulbs 5-47

Inspection Procedures 5-47

Pests 5-48

Muscari 5-54

Pest Risk Rating 5-54

Similar Looking Bulbs 5-54

Inspection Procedures 5-54

Pests 5-54

Narcissus 5-58

Pest Risk Rating 5-58

Similar Looking Bulbs 5-58

Inspection Procedures 5-58

Pests 5-59

Ornithogalum 5-67

Pest Risk Rating 5-67

Similar Looking Bulbs 5-67

Inspection Procedures 5-67

Pests 5-68

Oxalis 5-70

Pest Risk Rating 5-70

Similar Looking Bulbs 5-70

Inspection Procedures 5-70

Pests 5-71

Puschkinia 5-72

Pest Risk Rating 5-72

Similar Looking Bulbs 5-72

Inspection Procedures 5-72

Pests 5-72

Scilla 5-75

Pest Risk Rating 5-75

Similar Looking Bulbs 5-76

Inspection Procedures 5-76

Pests 5-76
True Bulbs

Introduction

10/2011-01 Bulb Identification Manual 5-3

Sprekelia 5-79

Pest Risk Rating 5-79

Similar Looking Bulbs 5-79

Inspection Procedures 5-79

Pests 5-80

Tigridia 5-81

Pest Risk Rating 5-81

Similar Looking Bulbs 5-81

Inspection Procedures 5-81

Pests 5-81

Tulipa 5-84

Pest Risk Rating 5-84

Similar Looking Bulbs 5-84

Inspection Procedures 5-85

Pests 5-85

Zephyranthes 5-99

Pest Risk Rating 5-99

Similar Looking Bulbs 5-99

Inspection Procedures 5-99

Pests 5-100

Introduction

True bulbs are underground, upright stems with fleshy modified leaves. The 

leaves can be layered around each other with the outer leaves often drying out 

(the tunic). These are known as tunicated bulbs. An onion, cut in cross 

sections, will show concentric rings where the leaves wrap around each other.

Figure 5-1 Sketch of a Lateral View and a Cross Sectional View of a True Bulb
True Bulbs

Introduction

5-4 Bulb Identification Manual 10/2011-01

In some true bulbs the fleshy leaves overlap each other and do not encircle the 

central bud or each other. Such bulbs are known as scaly bulbs. A lily is an 

example of this type of bulb.

When a true bulb starts to grow, roots usually emerge from the base of the bulb. 

The central bud sends up new leaves. The leaves collect food which is then 

stored in the bases of the growing leaves. This storage area, located in the bulb, 

expands. The outer leaf bases do not send up leaves. They dry up to form a 

protective papery covering (tunic).

Figure 5-2 Sketch of a True Bulb, the Lily

Figure 5-3 Steps in the Life Cycle of a True Bulb
True Bulbs

Introduction

10/2011-01 Bulb Identification Manual 5-5

The information in this chapter includes the pest risk rating for each bulb. The 

ratings are:

Identification Procedure

Determine the length of the bulb you are identifying. Compare it with the 

photographs in this chapter and select the description that fits your bulb. Each 

description includes inspection procedures and pests of concern.

Table 5-1 Pest Risk Ratings for True Bulbs

Pest Risk Rating

1–2 Very low risk. Verify the genus in the shipment. Inspect if time is available.

3–4 Low risk. Inspect if time is available.

5–6 Moderate risk. Provide normal inspection.

7–8 High risk. Inspect thoroughly.

9–10 Very high risk. Inspect very thoroughly.
True Bulbs

Allium (flowering onion)

5-6 Bulb Identification Manual 10/2011-01

Allium (flowering onion)

Allium bulbs are highly variable in size and shape depending on species and 

variety, but are generally broadly teardrop-shaped to globose, often very 

symmetrical, usually with a prominent apex. The tunic is papery or hard and 

shell-like, and often shiny. The bulb has a small root plate. In cross-section the 

bulb has few concentric rings. When cut, the bulb emits an onion-like odor, 

and the consistency of the moisture in the bulb may vary from liquid to 

viscous.

Pest Risk Rating

The pest risk rating for Allium is 6–7.

Source: USDA-APHIS

Figure 5-4 Allium (top to bottom): Allium karataviense; A. sphaerocephalon; A. 

moly; A. neapolitanum
True Bulbs

Allium (flowering onion)

10/2011-01 Bulb Identification Manual 5-7

Similar Looking Bulbs

Small species and varieties of Allium are similar in size and shape to many 

small bulbs, such as some varieties of Chionodoxa, Ornithogalum, and 

Puschkinia; however, they can be distinguished by their often shiny white tunic 

and onion-like scent when cut. Medium and large bulbed Allium are fairly 

distinctive.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal bulbs for inspection.

3. Peel back loose skin and examine the base of the bulb for brown streaking. 

The single streak or many streaks in the bands may spread from the base 

into the top of the bulb. Tweeze the damaged area in a dish of water to 

extract nematodes.

4. Look for aphids, mites, thrips, and signs of other pests or diseases.

Pests

Common Pests

Fusarium oxysporum. Symptoms: Rotting and discoloration usually beginning at 

the basal plate and proceeding upward towards apex of the bulb.

Mechanical injury. Symptoms: Scarring and abrasions due to damage sustained 

during harvest and cleaning. Mechanical injury is the most common disorder in 

Allium.

Source: (left photo) PPO; (right photo) USDA-APHIS

Figure 5-5 Fusarium oxysporum on Allium
True Bulbs

Allium (flowering onion)

5-8 Bulb Identification Manual 10/2011-01

Source: USDA-APHIS

Figure 5-6 Mechanical Damage on Different Varieties of Allium

source: USDA-APHIS

Figure 5-7 Mechanical Damage on Allium moly1

1 Mechanical damage on Allium moly. The left bulb shows the tunic intact; bulbs to the right 

show progressive degeneration of the bulbs (tunics removed) due to injury. Bulb on extreme 

right has become totally discolored and shrunken. Symptoms can be mistaken for Fusarium. 
True Bulbs

Allium (flowering onion)

10/2011-01 Bulb Identification Manual 5-9

Penicillium. Symptoms: Blue-green mold.

Rare Pests

Aphelenchoides subtenuis. Symptoms: Discoloration at basal plate, streaking 

upward; eventually the basal portion of the bulb becomes sunken but not soft. 

Diseases tissue turns grayish but not brown, as in Ditylenchus. Note 

characteristic shrinking of the base of the bulbs. Bulb in the top right photo has 

a secondary infection of Penicillium.

Source: USDA-APHIS

Figure 5-8 Penicillium on Allium

Source: (top left) PPO; (top right) BKD; (bottom) USDA-APHIS

Figure 5-9 Aphelencoides subtenuis on Allium
True Bulbs

Allium (flowering onion)

5-10 Bulb Identification Manual 10/2011-01

Aspergillus. Symptoms: Black mold.

Other Pests

Aceria tulipae. Symptoms: Reddish russeting of the bulb.

Aphids. Symptoms: No definite symptoms, live insects must be found.

No photo available.

Source: USDA-APHIS

Figure 5-10 Aspergillus on Allium moly

Source: BKD

Figure 5-11 Aceria tulipae Symptoms on Allium
True Bulbs

Allium (flowering onion)

10/2011-01 Bulb Identification Manual 5-11

Botrytis. Symptoms: Gray mycelia with black sclerotia.

No photo available.

Ditylenchus dipsaci. Symptoms: Discoloration of leaf scales, forming brown 

rings in cross section of the bulb. Discoloration at the basal plate, streaking 

towards apex. Basal area becomes soft.

Erwinia. Symptoms: Soft rot of bulb.

No photo available.

Gummosis. Symptoms: Clear or resin-like exudate. Often a reaction to injury. 

Note scarring due to mechanical injury.

Source: BKD

Figure 5-12 Ditylenchus dipsaci on Allium
True Bulbs

Allium (flowering onion)

5-12 Bulb Identification Manual 10/2011-01

Sclerotium cepivorum. Symptoms: White fluffy mycelia and masses of black 

sclerotia at the base of the bulb.

Thrips. Symptoms: Russeting of leaf scales.

No photo available.

Source: USDA-APHIS

Figure 5-13 Gummosis on Allium

Source: PPO

Figure 5-14 Sclerotium cepivorum on Allium
True Bulbs

Camassia

10/2011-01 Bulb Identification Manual 5-13

Camassia

The bulbs of Camassia vary in size and shape depending on species. Bulbs are 

1–2.25 inches (2.5–5.8 cm) tall and 1–2.25 inches (2.5–6.2 cm) wide. 

Generally, they are irregularly broadly teardrop in shape and often flattened on 

one side, with thin, papery dark brown tunic and a prominent basal plate. The 

tunic is often partially removed during post-harvest handling and the white 

inner scales are frequently marked by brown discolorations due to mechanical 

damage. The bulbs can be symmetrical or somewhat flattened on one or two 

sides. There are no serious problems with Camassia.

Pest Risk Rating

The pest risk rating for Camassia is 3.

Similar Looking Bulbs

There are none.

Inspection Procedures

1. Check consignment and verify lot.

Source: USDA-APHIS

Figure 5-15 Camassia leichtlinii
True Bulbs

Camassia

5-14 Bulb Identification Manual 10/2011-01

2. Look for soil contamination and select any abnormal bulbs for inspection.

3. Examine inner and outer scales for major pests.

Pests

Common Pests

None

Rare Pests

Ditylenchus destructor. Symptoms: Brown dry decay around roots. In cross 

section, the symptoms resemble those of a mild and dry Fusarium infection. 

Unlike in most other bulbs, there are no discolored concentric rings. 

Other Pests

None

Source: BKD

Figure 5-16 Camassia with Ditylenchus destructor1 2

1 Left photo: Infection of D. destructor on the right side of the basal plate.

2 Right photo: Longitudinal section of bulb showing Ditylenchus symptoms that resemble those 

of Fusarium.
True Bulbs

Chionodoxa

10/2011-01 Bulb Identification Manual 5-15

Chionodoxa

Chionodoxa bulbs are small, symmetrical, nearly globose to teardrop-shaped 

bulbs, about 1/2–1 inch (1.27–2.5 cm) in diameter, often with a pointed apex 

and a large basal plate. The tunic is whitish to cream-colored or brownish and 

papery. Fleshy leaf scales may have purple spots on damaged areas. A crosssection of the bulb reveals yellow material between the leaf scales and at the 

core of the bulb.

Pest Risk Rating

The pest risk rating for Chionodoxa is 5.

Similar Looking Bulbs

Chionodoxa bulbs may resemble those of Ornithogalum, Puschkinia, or some 

varieties of Allium.

Inspection Procedures

1. Check consignment and verify lot.

2. Check for soil contamination and select abnormal bulbs for inspection.

3. Cut the tip of the bulb off in a small cross-section to check for nematodes. 

The death of the growing tip of the bulb leaves a hard black, dry material in 

the core of the bulb.

Pests

Source: USDA-APHIS

Figure 5-17 Chionodoxa
True Bulbs

Chionodoxa

5-16 Bulb Identification Manual 10/2011-01

Common Pests

Penicillium. Symptoms: Blue-green mold, especially on damaged areas. This is 

normally a storage problem.

Rare Pests

None

Other Pests

Aphelenchoides. Symptoms: Discoloration and streaking at the base of the bulb.

No photo available.

Ditylenchus dipsaci. Symptoms: Discoloration of leaf scales, forming brown 

rings in cross section of the bulb. Discoloration at the basal plate, streaking 

upwards toward the apex. Eventually, the base of the bulb begins to shrink and 

crack at the basal plate. Note the cracking at the base of the bulb in 

Figure 5-19.

Source: USDA-APHIS

Figure 5-18 Penicillium on Chionodoxa
True Bulbs

Chionodoxa

10/2011-01 Bulb Identification Manual 5-17

Source: BKD

Figure 5-19 Ditylenchus dipsaci on Chionodoxa
True Bulbs

Fritillaria

5-18 Bulb Identification Manual 10/2011-01

Fritillaria

Fritillaria bulbs vary in size and shape depending on species. The bulbs of 

smaller species consist of two to three fat, large storage leaves. Bulbs of larger 

species have a thick donut-shaped outer scale and three to four thick inner leaf 

scales. Fritillaria bulbs lack papery tunics, are white to yellow in color, and 

emit a peculiar odor. In some species, there is a a prominent “flower stalk hole” 

at the center of the bulb. There is no tunic, so mechanical damage can be a 

serious problem.

Source: USDA-APHIS

Figure 5-20 Fritillaria imperialis (top left); F. uva vulpis (top right); F. meleagris

(bottom)
True Bulbs

Fritillaria

10/2011-01 Bulb Identification Manual 5-19

Pest Risk Rating

The pest risk rating for Fritillaria is 4.

Similar Looking Bulbs

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination, particularly in the cavity at the center of the 

bulb, and select abnormal bulbs for inspection.

3. Examine outer scales for disease.

Pests

Common Pests

Fusarium. Symptoms: Infections usually begin at the base of the bulb, 

spreading into the core. Infected areas are often edged with distinct roundish or 

lobe-like brown margins, and often characterized by concentric “growth 

rings.” 
True Bulbs

Fritillaria

5-20 Bulb Identification Manual 10/2011-01

Mechanical damage. Symptoms: The fleshy outer scales of Fritillaria are easily 

bruised or damaged. Superficial scars and lesions are often mistaken for 

Fusarium, but damaged areas lack the characteristic margins and concentric 

“growth rings.”

Source: (top photo) PPO; (bottom photo) USDA-APHIS

Figure 5-21 Fusarium on F. meleagris (top)1 and F. imperialis (bottom)2

1 Top photo: Fusarium on F. meleagris.

2 Bottom photo: basal infection of Fusarium on F. imperialis. Note concentric growth rings.
True Bulbs

Fritillaria

10/2011-01 Bulb Identification Manual 5-21

Rare Pests

Penicillium. Symptoms: Blue-green mold on damaged outer scales.

Other Pests

Sclerotinia bulborum. Symptoms: Infected areas with masses of gray or white 

mycelia and black sclerotia.

No photo available.

Source: USDA-APHIS

Figure 5-22 Mechanical Damage on Fritillaria imperialis

Source: USDA-APHIS

Figure 5-23 Penicillium on Fritillaria uva vulpis
True Bulbs

Galanthus

5-22 Bulb Identification Manual 10/2011-01

Galanthus

The bulbs of Galanthus are teardrop-shaped with a broad basal plate and 

slightly asymmetrical due to the development of daughter bulbs. The tunic is 

often glossy, dark to medium brown, with prominent veins. Leaf scars are 

visible on the apex of the outer leaf scales of the bulb.

Pest Risk Rating

The pest risk rating for Galanthus is 4.

Similar Looking Bulbs

Galanthus may resemble some varieties of Chionodoxa or small Narcissus.

Inspection Procedures

1. Check the consignment and verify lot.

2. Check for soil contamination and select abnormal bulbs for inspection.

3. Examine outer scales for disease.

Source: USDA-APHIS

Figure 5-24 Galanthus nivalis (top); G. elwesii (middle); G. woronowi (bottom)
True Bulbs

Galanthus

10/2011-01 Bulb Identification Manual 5-23

Pests

Common Pests

Fusarium. Symptoms: Dark, punky rot, usually from the base.

Rare Pests

Botrytis galanthina. Symptoms: Gray mold and round, flattened black sclerotia 

on outer scales, and a hard, dry root plate.

Source: BKD

Figure 5-25 Fusarium on Galanthus nivalis (tunic removed)

Source: PPO

Figure 5-26 Botrytis galanthina on Galanthus
True Bulbs

Galanthus

5-24 Bulb Identification Manual 10/2011-01

Stagonospora curtisii. Symptoms: Red or reddish brown spots that develop into 

lesions, usually with distinct margins.

No photo available.

Other Pests

Ditylenchus dipsaci. Symptoms: Discoloration at base of bulb, streaking upward. 

In cross section, infected scales appear as brown rings.

Sclerotium. Symptoms: Fluffy white mycelia and black sclerotia at base of bulb. 

No photo available.

Merodon equestris. Symptoms: Small hole at base of bulb; larva can be found 

eating its way through the interior of the bulb.

No photo available.

Source: BKD

Figure 5-27 Ditylenchus dipsaci on Galanthus nivalis (tunic removed) 
True Bulbs

Galtonia

10/2011-01 Bulb Identification Manual 5-25

Galtonia

Galtonia bulbs are broadly ovoid or teardrop-shaped with a prominent basal 

plate. The tunic and outer leaf scales are brownish to white with the top half 

being thin and papery, and the bottom half somewhat fleshy. The neck is thick 

with distinct veins on the tunic. In a cross section each scale is thick and firm; 

the vascular bundles are visible.

Pest Risk Rating

The pest risk rating for Galtonia is 4.

Similar Looking Bulbs

Hyacinth bulbs are similar. Galtonia veins are more pronounced and the root 

plate is thicker. When cut, Galtonia does not ooze like Hyacinth. Galtonia are 

usually shipped in the winter and spring; Hyacinth in the summer and fall.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal bulbs for inspection.

Source: USDA-APHIS

Figure 5-28 Galtonia
True Bulbs

Galtonia

5-26 Bulb Identification Manual 10/2011-01

3. Cut the tip of the bulb off in a cross section. Look for brown ring or 

discoloration. This may indicate the nematode, Ditylenchus dipsaci.

4. Fusarium may be present on the mummified bulbs. Fusarium has a 

distinct, sweet sour smell.

Pests

Common Pests

Fusarium. Symptoms: Dark brown discoloration beginning at base of bulb; 

often accompanied by a distinct, sweet sour smell.

Penicillium. Symptoms: Blue-green mold, usually secondary on damaged areas.

No photo available.

Rare Pests

Erwinia carotovora. Symptoms: Soft rot accompanied by fetid odor.

No photo available.

Other Pests

Ditylenchus dipsaci. Symptoms: Discoloration beginning at basal plate and 

streaking upward. In cross section, infected leaf scales appear as brown rings.

No photo available.

Source: BKD

Figure 5-29 Fusarium on Galtonia
True Bulbs

Hippeastrum

10/2011-01 Bulb Identification Manual 5-27

Hippeastrum

The bulbs of Hippeastrum are round and symmetrical with a long, flattened 

neck and long fleshy roots. The top 1/4 of the external leaf scale is papery, the 

lower 3/4 is fleshy. The bulb develops a red tinge on damaged areas. Vascular 

bundles are clearly visible on the cut leaves. Do not cut this bulb to identify.

Hippeastrum is commonly referred to as “Amaryllis.” However, the genus 

Amaryllis originated in South Africa, whereas the genus Hippeastrum is native 

to South America.

Pest Risk Rating

The pest risk rating for Hippeastrum is 6.

Similar Looking Bulbs

Amaryllis is similar; however, bulbs in the genus Amaryllis are conspicuously 

fibrous and smaller than those in Hippeastrum.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal bulbs for inspection.

3. Look in dried material at the neck for mealybugs, aphids, and thrips.

Source: USDA-APHIS

Figure 5-30 Hippeastrum
True Bulbs

Hippeastrum

5-28 Bulb Identification Manual 10/2011-01

4. Squeeze the neck of the bulb to open the leaf bases. Do not cut the bulb 

unless symptoms indicate major pests.

5. Examine the base of the bulb for a slightly depressed, corky area with a 

hole in it. This is a sign of the bulb fly.

Pests

Common Pests

Stagonospora curtisii. Symptoms: Red or reddish-brown spots that develop into 

lesions, usually with distinct margins. Any injury usually produces a red 

pigment, so red streaks or irregular patterns are not always indicative of 

Stagonospora infections. 
True Bulbs

Hippeastrum

10/2011-01 Bulb Identification Manual 5-29

Rare Pests

Steneotarsonemus laticeps. Symptoms: Reddish pinpoints at the edges of scales 

in cross section neck of bulb; reddish streaks along leaf scales in longitudinal 

section of bulb.

Source: (top photo) PPO; (bottom photo) BKD

Figure 5-31 Stagonospora curtisii on Hippeastrum1 2

1 Top photo: Left bulb, longitudinal section showing infection on scales originating at top and 

spreading toward the base. Right bulb, cross section of neck showing infected leaf scales. 

2 Bottom photo: Heavily infected bulb, cross section of top of bulb, just below the neck.
True Bulbs

Hippeastrum

5-30 Bulb Identification Manual 10/2011-01

Other Pests

Ditylenchus dipsaci. Symptoms: Red streaks that run from the top toward the 

base on the inner parts of scales.

No photo available.

Pseudococcidae (mealybugs). Symptoms: White floss on emerging leaves.

Source: PPO

Figure 5-32 Steneotarsonemus laticeps on Hippeastrum1 2

1 Top photo: Cross section of neck showing reddish pinpoints between the leaf scales.

2 Bottom photo: Longitudinal section showing reddish streaking along the leaf scales.
True Bulbs

Hippeastrum

10/2011-01 Bulb Identification Manual 5-31

No photo available.

Syrphidae (bulb fly). Symptoms: Slightly depressed, corky area with a hole in it. 

Larvae can be found eating its way through the interior of the bulb. If only one 

large larva is found, it is probably Merodon equestris. If several are found, it is 

probably Eumerus.

No photo available.
True Bulbs

Hyacinthus

5-32 Bulb Identification Manual 10/2011-01

Hyacinthus

Hyacinthus are very symmetrical, globose or broadly ovate bulbs with a coneshaped tip and a thick root plate. The loose papery tunic may be red, white, or 

purple. Veins are not visible on the tunic. Dark colored bulbs are speckled or 

dusty looking. In a cross section, the leaf scales are moderate in size and exude 

a viscous substance. The dust and exudate of Hyacinthus contain oxalates that 

irritate the skin. When inspecting, wear gloves and do not touch eyes or nose.

Pest Risk Rating

The pest risk rating for Hyacinthus is 7.

Similar Looking Bulbs

Bulbs of Scilla siberica resemble Hyacinthus bulbs, but they are much smaller.

Inspection Procedures

1. The dust and exudate of Hyacinthus contain oxalates that irritate the skin. 

When inspecting, wear gloves and avoid touching eyes and nose.

2. Check consignment and verify lot.

3. Look for soil contamination and select abnormal bulbs for inspection.

4. Cut off the tip of the bulb in a cross-section and look for signs of 

nematodes, Erwinia, and Xanthomonas.

Source: USDA-APHIS

Figure 5-33 Hyacinthus
True Bulbs

Hyacinthus

10/2011-01 Bulb Identification Manual 5-33

Pests

Common Pests

Aspergillus niger. Symptoms: Black mold, commonly found just beneath the 

tunic; often secondary on injuries.

Erwinia carotovora. Symptoms: White-yellow, foul smelling ooze from inside 

bulb (variety ‘Blue Jacket’ is very susceptible; white skinned varieties also 

susceptible). Central rot at apex of bulb, eventually affecting the core and the 

entire bulb.

Source: USDA-APHIS

Figure 5-34 Aspergillus niger on Hyacinthus Variety with White Tunic
True Bulbs

Hyacinthus

5-34 Bulb Identification Manual 10/2011-01

Penicillium. Symptoms: Blue-green mold commonly found under the papery 

tunic. Mostly a storage problem.

Rare Pests

Fusarium. Symptoms: Brownish discoloration accompanied by a sweet, moldy 

odor; infection usually beginning at base of bulb and spreading through the 

interior.

Source: PPO

Figure 5-35 Erwinia carotovora on Hyacinthus

Source: USDA-APHIS

Figure 5-36 Hyacinthus with Penicillium
True Bulbs

Hyacinthus

10/2011-01 Bulb Identification Manual 5-35

Rhodocoddus fascians. Symptoms: Fasciations around the basal plate.

Source: (top photo) PPO; (bottom photo) J. Heuperman

Figure 5-37 Fusarium on Hyacinthus1 2

1 Top photo: Exterior symptoms; bulbs with tunic removed.

2 Bottom photo: Longitudinal section of bulb.

Source: PPO

Figure 5-38 Rhodococcus on Hyacinthus
True Bulbs

Hyacinthus

5-36 Bulb Identification Manual 10/2011-01

Other Pests

Ditylenchus dipsaci. Symptoms: Discoloration of leaf scales, forming brown 

rings in cross section of bulb.

Embellesia. Symptoms: Circular brown spots not penetrating outer tunic.

No photo available.

Erwinia rhapontica. Symptoms: Yellow discoloration of the upper portion of the 

central leaf scales (‘Anne Marie’ is very susceptible). Infection never goes to 

the base of the bulb. Strictly a quality issue; does not affect flowering. There is 

no fetid odor as in E. carotovora.

Source: (top photo) PPO; (bottom photo) BKD

Figure 5-39 Cross Section of Hyacinthus Bulbs Showing Discolored Leaf 

Scales Caused by Infection of Ditylenchus dipsaci
True Bulbs

Hyacinthus

10/2011-01 Bulb Identification Manual 5-37

Sclerotinia bulborum. Symptoms: Infected areas with masses of gray or white 

mycelia and black sclerotia.

No photo available.

Thysanoptera (thrips). Symptoms: Russeting of the affected leaf scales.

Source: BKD

Figure 5-40 Erwinia rhapontica on Hyacinthus
True Bulbs

Hyacinthus

5-38 Bulb Identification Manual 10/2011-01

Xanthomonas campestris pv hyacinthi. Symptoms: Yellow odorless ooze from 

inside bulb. Discoloration of core of bulb. Infections may begin at the base of 

the bulb or from the apex. Infection of the bulb can be easily transmitted in 

storage and by infected machinery. Infections of the apex begin at the apex, the 

bacterium having traveled down from the leaves. It can easily be transmitted 

by walking through wet fields during field inspections.

Source: PPO

Figure 5-41 Thrip Damage Along Inner Scales on Hyacinth (outer leaf scales 

removed)
True Bulbs

Hyacinthus

10/2011-01 Bulb Identification Manual 5-39

Source: BKD

Figure 5-42 Xanthomonas on Hyacinthus1 2

1 Top left and right photos: bulbs show symptoms of a bulb-type infection. .

2 Bottom photo: bulb shows symptoms of an apex type of infection
True Bulbs

Iris

5-40 Bulb Identification Manual 10/2011-01

Iris

Iris bulbs are more or less teardrop-shaped with a slender, prominent apex. The 

tunic is light to dark brown, usually fibrous, glossy and strongly veined. The 

tunic and fleshy scale wraps around the bulb like a coat and is sutured on one 

side. In a cross-section, the bulb has only two or three rings of fleshy leaf 

scales. The flesh is dry. These bulbs are often treated with fungicide.

Pest Risk Rating

The pest risk rating for Iris is 7.

Similar Looking Bulbs

None

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal bulbs for inspection.

3. Look at tunic and peel them down to see if mealybugs, aphids, or 

nematodes are present.

4. Examine the base of the bulb for nematode symptoms and Fusarium.

5. Cut the apex fo the bulb to reveal the inner fleshy scales. Look for 

nematode symptoms.

Source: USDA-APHIS

Figure 5-43 Iris: (top row) Iris danfordii; (bottom row) Iris reticulata
True Bulbs

Iris

10/2011-01 Bulb Identification Manual 5-41

Pests

Common Pests

Fusarium. Symptoms: A sunken area around the basal plate with brown rot and 

white mycelia.

Penicillium. Symptoms: Blue-green mold.

Source: PPO

Figure 5-44 Advanced Infection of Fusarium on Iris

Source: USDA-APHIS

Figure 5-45 Penicillium on Iris
True Bulbs

Iris

5-42 Bulb Identification Manual 10/2011-01

Rare Pests

None

Other Pests

Aphids. Symptoms: Sticky bulbs may indicate aphid infestation but live insects 

must be found.

Ditylenchus destructor. Symptoms: Gray to black streaks radiating from the 

base; or a reddish ring or spot in cross section of bulb at the apex.

Source: PPO

Figure 5-46 Aphid Damage on Iris1

1 Live insects can be found at base and apex on left bulb.
True Bulbs

Iris

10/2011-01 Bulb Identification Manual 5-43

Dreschslera iridis. Symptoms: Irregular ink blot spots and streaking on tunic and 

outer scales if the infection is severe.

Source: nVWA

Figure 5-47 Ditylenchus destructor on Iris1

1 Left bulb: characteristic streaking from base of bulb. Right bulb: advanced stage of infection 

with base of bulb beginning to shrink.

Source: PPO

Figure 5-48 Dreschslera iridis on Iris1
True Bulbs

Iris

5-44 Bulb Identification Manual 10/2011-01

Mealybugs. Symptoms: White floss; apparent particularly when bulbs have 

been stored at 30 °C for a long period of time.

1 Right two bulbs are healthy; four on left are infected.

Source: PPO

Figure 5-49 Iris Bulbs Severely Infected with Mealybugs

Source: PPO

Figure 5-50 Iris Bulbs with Phenacoccus avenae1

1 Left: healthy bulb. Center and right bulbs infested with P. avenae.
True Bulbs

Iris

10/2011-01 Bulb Identification Manual 5-45

Plodia interpunctella. Symptoms: Appearance of frass.

Sclerotinia bulborum. Symptoms: Infected areas with masses of gray or white 

mycelia and black sclerotia.

No photo available.

Sclerotium. Symptoms: White mycelia and masses of black sclerotia.

Source: PPO

Figure 5-51 Plodia interpunctella on Iris1

1 Frass indicating an infestation of P. interpunctella or another interal feeder.
True Bulbs

Iris

5-46 Bulb Identification Manual 10/2011-01

Source: PPO

Figure 5-52 Sclerotium wakkeri on Iris Bulbs1

1 Note masses of sclerotia forming on black infected areas. Bulb on bottom left is healthy.
True Bulbs

Lilium

10/2011-01 Bulb Identification Manual 5-47

Lilium

Lilium bulbs are very distinctive, being made up of many overlapping fleshy 

scales. The scales can be stiff or somewhat flexible and may be white, yellow, 

red, or purple. Roots are often attached to the base. Do not cut into this bulb to 

identify it. Lilium bulbs may be dipped in fungicide and pesticide before 

storage.

Pest Risk Rating

The pest risk rating for Lilium is 6.

Similar Looking Bulbs

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal bulbs for inspection.

3. Examine outer scales for disease.

Source: USDA-APHIS

Figure 5-53 Different Varieties of Lilium
True Bulbs

Lilium

5-48 Bulb Identification Manual 10/2011-01

4. Look at the root plate and roots for disease and nematode symptoms.

5. Pry open scales. Look for thrips, snails, slugs, and other surface feeders, 

and soil. Do not break off the scales needlessly.

6. If the scales are rosetted or discolored, examine the center scales near the 

growing point for nematodes.

Pests

Common Pests

Fusarium. Symptoms: Brown basal rot causing scales to fall off. Infection 

begins at the outer scales, spreading towards the apex and into the interior of 

the bulb. Cylindrocarpon is often associated with Fusarium infections and 

laboratory tests for Fusarium will normally be positive for Cylindrocarpon, as 

well. Fusarium is much more aggressive and severe symptoms will appear 

much earlier than those for Cylindrocarpon.

Figure 5-54 Lilium Bulbs Infected with Fusarium1 2 3

1 Top left photo: Typical symptoms with infection beginning at the base of the outer scales and 

surrounding the basal plate. Source: nVWA

2 Top right photo: Cross section of bulbs just above basal plate showing Fusarium infections 

of upper right leaf scales. Infection on right bulb is still confined to the base of the leaf scales. 

Infection on left bulb has spread into the core. Source: USDA-APHIS

3 Bottom photo: Example of mixed infection of Cylindrocarpon and Fusarium. Source: PPO
True Bulbs

Lilium

10/2011-01 Bulb Identification Manual 5-49

Rare Pests

Aphelenchoides. Symptoms: Rosetting of scales. Scales often become 

abnormally spaced. “Loose” scales may also be symptomatic of other 

disorders, so samples should be sent to the laboratory for identification.

Penicillium. Symptoms: Blue-green mold usually secondary on damaged areas 

that are usually chocolate brown in color; resulting in a dry, punky rot. Usually 

a storage problem.

Source: nVWA

Figure 5-55 Aphelenchoides on Lilium1

1 Note the slightly abnormal arrangement of scales and wide spacing.
True Bulbs

Lilium

5-50 Bulb Identification Manual 10/2011-01

Rhizoglylphus robinii. Symptoms: Holes through the leaf scales. In severe 

infestations, the scales begin to fall off.

Rhodococcus fascians. Symptoms: Abnormal, swollen ribbing and fasciations 

of the basal leaf scales and proliferation of fasciated tissue at base of bulb.

Source: nVWA

Figure 5-56 Lilium with Penicillium Forming as a Result of Mechanical Damage

Source: BKD

Figure 5-57 Rhizoglyphus robinii Symptoms on Lilium1

1 Note conspicuous brownish black holes.
True Bulbs

Lilium

10/2011-01 Bulb Identification Manual 5-51

Other Pests

Botrytis. Symptoms: Gray or grayish-brown mycelia and black sclerotia; brown 

rotting of scales.

Source: (top photos) BKD; (bottom photo) USDA-APHIS

Figure 5-58 Rhodococcus on Lilium
True Bulbs

Lilium

5-52 Bulb Identification Manual 10/2011-01

Pratylenchus. Symptoms: Lesions on roots.

No photo available.

Thrips. Symptoms: Russeting on leaf scales.

Source: PPO

Figure 5-59 Botrytis cineria on Lilium
True Bulbs

Lilium

10/2011-01 Bulb Identification Manual 5-53

Source: PPO

Figure 5-60 Lilium with Outer Scales Removed, Showing Characteristic 

Russeting and Live Adult Thrips
True Bulbs

Muscari

5-54 Bulb Identification Manual 10/2011-01

Muscari

Muscari bulbs are symmetrical to irregular, teardrop to globose in shape, with 

a whitish to pinkish papery or somewhat fleshy tunic. The base of the bulb is 

large in comparison to the size of the bulb, and the basal plate is broad, often 

with many fibrous roots. The inner scales are soft and thick, with no viscous 

exudates.

Pest Risk Rating

The pest risk rating for Muscari is 5.

Similar Looking Bulbs

Smaller species of Muscari may resemble some species of Ornithogalum, but 

Ornithogalum bulbs usually exude a sticky sap.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal bulbs for inspection.

3. Examine outer scales.

4. Examine root plate.

5. Peel off the scales.

6. Cut enough of the apex of the bulb to reveal the inner fleshy scales.

Pests

Common Pests

Fusarium. Symptoms: Dark brown basal rot.

Source: USDA-APHIS

Figure 5-61 Muscari armeniaca (left); M. comosum “Plumosum” (right)
True Bulbs

Muscari

10/2011-01 Bulb Identification Manual 5-55

Rare Pests

Penicillium. Symptoms: Blue-green mold, often on damaged areas.

Rhodococcus fascians. Symptoms: Fasciations and proliferation of small 

abnormal bulbs around the basal plate.

Source: BKD

Figure 5-62 Fusarium on Muscari armeniacum

Source: USDA-APHIS

Figure 5-63 Penicillium on Muscari armeniacum
True Bulbs

Muscari

5-56 Bulb Identification Manual 10/2011-01

Other Pests

Ditylenchus dipsaci. Symptoms: Discoloration of the leaf scales forming brown 

rings in a cross section.

Source: BKD

Figure 5-64 Rhodococcus fascians on Muscari

Source: PPO

Figure 5-65 Ditylenchus dipsaci on Muscari1

1 Right two bulbs in cross section showing discolored rings; Left two bulbs in longitudinal section showing infected leaf scales.
True Bulbs

Muscari

10/2011-01 Bulb Identification Manual 5-57

Nose Rot. Symptoms: Soft rot of the central leaf scales, rarely penetrating 

beyond the middle of the bulb.

Sclerotium bulborum. Symptoms: Gray or grayish-brown areas on bulb, 

becoming dark brown; large brown sclerotia at apex. Causes a dry rot of the 

bulb.

No photo available.

Source: BKD

Figure 5-66 Nose Rot on Muscari1

1 Left photo: cross section of neck showing discoloration of scales. Right photo: longitundinal 

section of bulb showing infected scales.
True Bulbs

Narcissus

5-58 Bulb Identification Manual 10/2011-01

Narcissus

Narcissus bulbs are more or less teardrop-shaped to nearly globose, and are 

highly variable in size; 1/4–4 inches (7–100 mm) in diameter at the base. Some 

varieties are irregular in shape because they divide frequently during the 

growing season, while others do not produce many daughter bulbs and are 

quite symmetrical. The bulbs are characterized by light to dark or reddishbrown or graying papery tunic marked with distinct dark veins, and a corky, 

large root plate. When cut, the bulb profusely bleeds a sticky mucilage and the 

cut surface eventually becomes black.

Pest Risk Rating

The pest risk rating for Narcissus is 8–9.

Similar Looking Bulbs

Small varieties of Narcissus may resemble large Galanthus.

Inspection Procedures

Source: USDA-APHIS

Figure 5-67 Narcissus
True Bulbs

Narcissus

10/2011-01 Bulb Identification Manual 5-59

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal bulbs for inspection.

3. Look at basal plate for evidence of internal feeders.

4. Examine outer scales for disease.

5. Peel a few dried scales from the base to reveal the fleshy scales. 

Discoloration at the base may indicate disease or mites.

6. Cut enough of the apex to remove dry leaf remnants and reveal inner fleshy 

scales. Look for nematode and mite symptoms.

Pests

Common Pests

Bruising. Symptoms: Spotty gray-black discoloration on exterior of bulb 

resulting from damage sustained during harvest and cleaning. Damage is 

restricted to outer scales. The papery tunic must be removed to observe the 

symptoms. Some varieties are extremely susceptible to bruising.

Fusarium. Symptoms: Soft, dry, chocolate or purplish brown rot usually 

beginning at the base of the bulb, sometimes at the neck; often accompanied by 

white mycelia. Bulbs infected with Fusarium become soft and spongy. Tunic 

must be at least partially removed or the bulb must be cut in cross section to 

see the symptoms.

Source: USDA-APHIS

Figure 5-68 Bruising on Narcissus
True Bulbs

Narcissus

5-60 Bulb Identification Manual 10/2011-01

Rare Pests

Steneotarsonemus laticeps. Symptoms: Browning and peeling in crevasses 

between leaf scales; yellowish or brownish discoloration along scales. The 

lateral compression of the leaf scales in the bulb create small gaps between the 

scales at the edges (the “v” ends of the concentric rings). Normally the mites 

gain entry into the bulb through this channel. Bulbs must be cut at the neck to 

see the symptoms.

Source: USDA-APHIS

Figure 5-69 Fusarium on Narcissus1 2 3

1 Top left photo: Both bulbs are infected with Fusarium, but symptoms on bulb on the left are 

hidden by the outer tunic. Symptoms are evident on bulb on the right, with outermost tunic 

removed. Note white mycelia. 

2 Top right photo: Cross section at middle of the bulb showing typical discoloration of tissue.

3 Bottom photo: Longitudinal section of bulb showing early stages of basal rot caused by Fusarium.
True Bulbs

Narcissus

10/2011-01 Bulb Identification Manual 5-61

Other Pests

Aphelenchoides subtenuis. Symptoms: Discoloration at the base of the bulb 

causing some cracking at the basal plate, but the bulb does not decay and 

become soft. Discoloration of the leaf scales causing cream-colored or grayish 

(not brown) rings in cross section of the bulb. Only certain varieties are 

susceptible.

Source: (top photos) PPO; (bottom photo) USDA-APHIS

Figure 5-70 Steneotarsonemus laticeps on Narcissus1 2 3

1 Top left photo: Longitundinal section of bulb showing discoloration along the leaf scale 

caused by mite damage. Damage occurs on the outer/inner edge of leaf scale. 

2 Top right photo: Cross section of bulb just below the neck shows advanced stages of Steneotarsonemus infestation. Affected areas are brown, becoming black as the tissue deteriorates.

3 Bottom photo: Cross section of bulb just below the neck showing early stages of infestation. 

Note early stages of infestation near the “v” ends of the leaf rings.
True Bulbs

Narcissus

5-62 Bulb Identification Manual 10/2011-01

Botrytis narcissicola. Symptoms: Soft, dry, yellowish to dark brown rot in the 

neck of the bulb that may extend to the base. Black sclerotia develop on or 

between the scales.

Ditylenchus dipsaci. Symptoms: Discoloration of the leaf scales, forming brown 

rings in cross section of the bulb. Basal portion of bulb becomes soft and 

completely rotted.

Source: BKD

Figure 5-71 Aphelenchoides subtenuis on Narcissus Showing Basal Plate 

Beginning to Separate from Bulb

Source: PPO

Figure 5-72 Botrytis narcissicola on Narcissus
True Bulbs

Narcissus

10/2011-01 Bulb Identification Manual 5-63

Horse Teeth. Symptoms: A physiological disorder that causes the bulb to 

produce a proliferation of small, non-viable bulbs.

Source: (top photo) PPO; (bottom photo) USDA-APHIS

Figure 5-73 Ditylenchus dipsaci on Narcissus1 2

1 Top photo: Left bulb shows longitudinal section showing infected scales. Right bulb is a cross 

section of neck of bulb showing characteristic discoloration of infected scales. 

2 Bottom photo: On left bulb note shrinking and cracking at basal plate. Cross section through 

middle of bulb on the right showing discolored scales in concentric rings.
True Bulbs

Narcissus

5-64 Bulb Identification Manual 10/2011-01

Rhizoglyphus echinopus. Symptoms: Rather large secondary mites (0.5–0.9 mm 

long), normally found in decayed portions of the bulb.

No photo available.

Sclerotinia bulborum. Symptoms: Infected areas with masses of gray or white 

mycelia and black sclerotia.

No photo available.

Sunburn. Symptoms: Blackish discoloration on surface of the bulb beneath the 

tunic. Damage restricted to only outer scales, rarely penetrating deeper than 

three scales.

Source: USDA-APHIS

Figure 5-74 “Horse Teeth” on Narcissus1

1 Left: normal bulb. Right: bulb with “horse teeth.”
True Bulbs

Narcissus

10/2011-01 Bulb Identification Manual 5-65

Syrphidae (bulb fly). Symptoms: A hole with frass at or near the base of the bulb. 

The bulb may become soft due to rotting and damage caused by the larva. 

Rotting may extend to the apex of the bulb and cutting the neck may reveal 

discolored tissue. Lesser Bulb Fly (Eumerus strigatus) is usually associated 

with bulbs that have been injured and are already decaying. Normally, more 

than one larva can be found. Larger Bulb Fly (Merodon equestris) is not

associated with decaying bulbs and only one large larva is found.

Source: PPO

Figure 5-75 Sunburn on Narcissus1

1 Top row: Bulbs with tunics removed, showing damage symptoms. Top left bulb also shows 

symptoms of bruising. Bottom left: Bulb with tunic only partially removed. Bottom right: Cross 

section showing damage restricted to outer two scales.
True Bulbs

Narcissus

5-66 Bulb Identification Manual 10/2011-01

Source: USDA-APHIS

Figure 5-76 Bulb Fly in Narcissus1 2 3

1 Top left and top right photos: Lesser Bulb Fly found in Narcissus bulbs that are already decaying. 

2 Bottom left photo: Larger Bulb Fly. Larva is much larger than that of Lesser Bulb Fly. Note 

lack of decayed material in bulb.

3 Bottom right photo: Basal plate is cut off to show entry hole of the larva. Note the lack of other 

exterior symptoms.
True Bulbs

Ornithogalum

10/2011-01 Bulb Identification Manual 5-67

Ornithogalum

Ornithogalum are teardrop-shaped to nearly globose bulbs with broad basal 

plates. Some species are nearly symmetrical while others are irregular due to 

the development of daughter bulbs. The top half of the external bulb scale is 

papery, the lower half is fleshy. Tunic can be white, gray, yellowish, or brown. 

The bulbs of some species may exude a somewhat sticky substance when 

damaged.

Pest Risk Rating

The pest risk rating for Ornithogalum varies according to species. The average 

rating is 4–6.

Similar Looking Bulbs

Ornithogalum is somewhat similar in size and shape to Puschkinia, but differs 

in tunic.

Inspection Procedures

Source: USDA-APHIS

Figure 5-77 Ornithogalum1

1 Top left photo: Ornithogalum thyrsoides. Bottom left photo: O. saundersiae. Right photo: O. 

arabicum.
True Bulbs

Ornithogalum

5-68 Bulb Identification Manual 10/2011-01

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal bulbs for inspection.

3. Examine outer scales for diseases, especially Sclerotinia bulborum.

4. Peel back scales to look for aphids.

5. For O. umbellatum, cut enough of apex to expose fleshy scales. Brown ring 

or spot indicates Ditylenchus dipsaci.

6. For O. thyrsoides and O. arabicum, look for roughened galls at the root 

plate as an indication of Meloidogyne.

Pests

Common Pests

None

Rare Pests

Fusarium. Symptoms: Soft brownish rot usually beginning at the base of the 

bulb.

Penicillium. Symptoms: Blue-green mold.

Source: BKD

Figure 5-78 Fusarium on Ornithogalum
True Bulbs

Ornithogalum

10/2011-01 Bulb Identification Manual 5-69

Other Pests

Ditylenchus dipsaci. Symptoms: Discoloration of leaf scales forming brown 

rings in cross section of the bulb.

No photo available.

Sclerotinia bulborum. Symptoms: Infected areas with masses of gray or white 

mycelia and black sclerotia.

No photo available.

Source: USDA-APHIS

Figure 5-79 Penicillium on Ornithogalum nutans
True Bulbs

Oxalis

5-70 Bulb Identification Manual 10/2011-01

Oxalis

Oxalis bulbs are very distinctive. Most species have a hairy basal plate. The 

tunic and outer scales can be fibrous, papery, or somewhat succulent, and the 

inner scales can be gummy or sticky and yellowish in color. There are no 

serious problems with Oxalis.

Pest Risk Rating

The pest risk rating for Oxalis is 3.

Similar Looking Bulbs

There are none.

Inspection Procedures

1. Check consignment and verify lot.

Source: USDA-APHIS

Figure 5-80 Oxalis adenophylla (top left); O. deppei (top right); O. triangularis

(bottom)
True Bulbs

Oxalis

10/2011-01 Bulb Identification Manual 5-71

2. Check for soil contamination and select abnormal bulbs for inspection.

3. Peel back outer scales from apex to the base to reveal the brown, sticky 

inner scales. Dark brown necrotic spots indicate the presence of 

nematodes.

Pests

Common Pests

None

Rare Pests

None

Other Pests

Aphelenchoides subtenuis (commonly found on O. deppi, O. sasiandra). Symptoms: 

Discoloration of the basal area.

No photo available.

Ditylenchus destructor (commonly found on O. deppi, O. lasiandra). Symptoms: 

Discoloration of the leaf scales.

No photo available.

Fusarium oxysporum (commonly found on O. adenophila). Symptoms: Brownish 

rot, usually basal.

No photo available.

Penicillium (commonly found on O. adenophila). Symptoms: Blue-green mold.

No photo available.
True Bulbs

Puschkinia

5-72 Bulb Identification Manual 10/2011-01

Puschkinia

Puschkinia are ovoid or teardrop-shaped, mostly symmetrical bulbs about 

0.75–1 inch (2–2.5 cm) in diameter and 1 inch (2.5 cm) tall. They are 

characterized by a whitish or dirty, papery tunic. In cross section, air pockets or 

locules are present in concentric rings. The flesh is white and translucent.

Pest Risk Rating

The pest risk rating for Puschkinia is 5–6.

Similar Looking Bulbs

Puschkinia bulbs may resemble some varieties of Allium or Ornithogalum

(especially O. balancae) bulbs in shape.

Inspection Procedures

1. Check consignment and verify lot.

2. Check for soil contamination and select abnormal bulbs for inspection.

3. Examine outer scales for Sclerotinia bulborum.

4. Cut enough of apex to reveal inner fleshy scales. Yellowish brown spots 

indicate Ditylenchus dipsaci.

Pests

Common Pests

None

Source: USDA-APHIS

Figure 5-81 Puschkinia libanotica
True Bulbs

Puschkinia

10/2011-01 Bulb Identification Manual 5-73

Rare Pests

Penicillium. Symptoms: Blue-green mold, usually the result of poor storage 

conditions.

Other Pests

Ditylenchus dipsaci. Symptoms: Discoloration of base of bulb, extending 

towards apex. Discoloration of leaf scales, forming rings in cross section of 

bulb; cross section at apex show yellowish-brown spots.

Source: USDA-APHIS

Figure 5-82 Penicillium on Puschkinia libanotica
True Bulbs

Puschkinia

5-74 Bulb Identification Manual 10/2011-01

Sclerotinia bulborum. Symptoms: Infected areas with gray or white mycelia and 

black sclerotia.

No photo available.

Source: BKD

Figure 5-83 Ditylenchus dipsaci on Puschkinia libanotica1

1 Note the brown discoloration extending from the basal plate.
True Bulbs

Scilla

10/2011-01 Bulb Identification Manual 5-75

Scilla

Several species of Scilla are commonly grown in the Netherlands. The most 

popular are S. siberica and S. campanulata. S. siberica bulbs are globose to 

teardrop-shaped and symmetrical with one or two reddish, paper tunic. The 

loose, crumbling, fine roots on the base break off easily. When damaged, the 

bulb exudes a sticky substance. S. campanulata are very irregular, lumpy, squat 

bulbs with thick, fleshy outer scales. The loose, crumbling, fine roots on the 

base break off easily. The root plate is recessed or flush with the base of the 

bulb, and the base of the bulb is expanded. S. mischtschenkoana resembles S. 

siberica, but the outer tunic is whiteish and the inner layers can be reddish. S. 

bifolia is a much smaller bulb resembling Puschkinia or some varieties of 

Ornithogalum.

Pest Risk Rating

Scilla has a pest risk rating of 4–5.

Source: USDA-APHIS

Figure 5-84 Scilla1 2

1 Top left photo: Scilla siberica. Top right photo: Scilla campanulata. 

2 Bottom photo, top row: Scilla meschtschenkoana; bottom photo, bottom row: Scilla bifolia.
True Bulbs

Scilla

5-76 Bulb Identification Manual 10/2011-01

Similar Looking Bulbs

Some varieties of Muscari may resemble Scilla mischtschenkoana while other 

varieties of Muscari and Chinodoxa may resemble S. bifolia. Scilla siberica

resembles small bulbs of Hyacinthus varieties with red tunics.

Inspection Procedures

1. Check consignment and verify lot.

2. Check for soil contamination and select abnormal bulbs for inspection.

3. Examine outer scales for disease symptoms.

4. Cut enough of the apex to reveal inner fleshy scales (25 bulbs). A brown 

ring indicates Ditylenchus dipsaci.

Pests

Common Pests

None

Rare Pests

Penicillium. Symptoms: Blue-green mold below the tunic.

Other Pests

Aspergillus niger. Symptoms: Black mold

Source: USDA-APHIS

Figure 5-85 Scilla with Penicillium
True Bulbs

Scilla

10/2011-01 Bulb Identification Manual 5-77

Ditylenchus dipsaci. Symptoms: Discoloration of leaf scales, forming a brown 

ring in cross section of the bulb.

No photo available.

Fusarium. Symptoms: Brown rot usually beginning at the base of the bulb.

No photo available.

Sclerotinia bulborum. Symptoms: Gray or white mycelia and black sclerotia.

Source: USDA-APHIS

Figure 5-86 Aspergillus on Scilla peruviana
True Bulbs

Scilla

5-78 Bulb Identification Manual 10/2011-01

Xanthomonas campestris pv. hyacinthi. Symptoms: Brownish-yellow 

discoloration of the core of the bulb (central scales).

Source: USDA-APHIS

Figure 5-87 Sclerotinia bulborum on Scilla siberica1

1 Note black sclerotia.

Source: BKD

Figure 5-88 Xanthomonas campestris pv hyacinthi on Scilla
True Bulbs

Sprekelia

10/2011-01 Bulb Identification Manual 5-79

Sprekelia

Sprekelia are ovoid or teardrop-shaped with a distinct long “neck.” The 1-1/2–

2 inch (38–50 mm) long bulb is symmetrical with reddish-brown outer papery 

tunic. The root plate is thick and roots are thin, short, and fibrous. If the bulb is 

cut or peeled, the inner fleshy scales are fibrous, white to gray in color, and 

slightly sticky.

Pest Risk Rating

The pest risk rating for Sprekelia is 7.

Similar Looking Bulbs

Narcissus

Inspection Procedures

1. Check consignment and verify lot.

Source: USDA-APHIS

Figure 5-89 Sprekelia
True Bulbs

Sprekelia

5-80 Bulb Identification Manual 10/2011-01

2. Check for soil contamination and select abnormal bulbs for inspection.

3. Examine outer scales for diseases. Examine fleshy scales for mites.

Pests

Common Pests

Steneotarsonemus laticeps. Symptoms: Reddish spots at edges of scales in cross 

section of neck of bulb; reddish streaks along the scales in longitudinal section 

of bulb.

Rare Pests

Stagonosporopsis curtisii. Symptoms: Reddish-brown spots developing into 

lesions, usually with distinct margins.

No photo available.

Other Pests

Ditylenchus dipsaci. Symptoms: Discoloration of leaf scales, forming rings in 

cross section of bulb.

No photo available.

Source: BKD

Figure 5-90 Longitudinal Section of Sprekelia Bulb Showing Characteristic Red 

Discoloration of Scales Affected by Steneotarsonemus laticeps
True Bulbs

Tigridia

10/2011-01 Bulb Identification Manual 5-81

Tigridia

Tigridia are asymmetrical bulbs, 1 to 1-1/2 inches (38–50 mm) in length, with 

tightly fitting papery leaf scales. The bulb often consists of two smaller bulbs 

wrapped tightly together by the leaf scales. The tunic is gray-brown to brown 

in color, leathery, and is often twisted around the bulb. Tigridia are shipped in 

the winter and spring.

Pest Risk Rating

The pest risk rating for Tigridia is 5–6.

Similar Looking Bulbs

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Check soil for contamination and select abnormal bulbs for inspection.

3. Examine outer scales for diseases.

4. Examine base for nematode symptoms. Brown to black streaking indicates 

the presence of Ditylenchus destructor.

5. Peel back scales at apex to look for aphids.

Pests

Source: USDA-APHIS

Figure 5-91 Tigridia
True Bulbs

Tigridia

5-82 Bulb Identification Manual 10/2011-01

Common Pests

None

Rare Pests

Aphids. Symptoms: No distinct symptoms; live insects must be found. 

Infestations of aphids occur during storage when populations build up from a 

few infested bulbs.

No photo available.

Fusarium. Symptoms: Brown rot at base of bulb.

Penicillium. Symptoms: Blue-green mold.

No photo available.

Other Pests

Ditylenchus destructor. Symptoms: Brown to black streaking from base of bulb.

Source: USDA-APHIS

Figure 5-92 Tigridia with Fusarium1

1 Left photo: View of base of bulbs. Right photo: Longitudinal section.
True Bulbs

Tigridia

10/2011-01 Bulb Identification Manual 5-83

Source: J. Heuperman

Figure 5-93 Ditylenchus destructor on Tigridia
True Bulbs

Tulipa

5-84 Bulb Identification Manual 10/2011-01

Tulipa

Tulipa are teardrop-shaped with a prominent, lopsided root plate slanted down 

on the side of the bulb. The tunic is either tough and leathery, papery or 

smooth, and red to tan to dark brown. In botanical tulips, the apex of the bulb is 

often topped with a cottony material and the tunic is very hard and difficult to 

break open. Do not needlessly peel off the tunics. Examine the bulb at cracked 

areas of the tunic.

Pest Risk Rating

The pest risk rating for Tulipa is 8.

Similar Looking Bulbs

There are none.

Source: USDA-APHIS

Figure 5-94 Four Different Types of Tulipa
True Bulbs

Tulipa

10/2011-01 Bulb Identification Manual 5-85

Inspection Procedures

1. Check consignment and verify lot.

2. Check for soil contamination and select abnormal bulbs for inspection.

3. Examine base for disease and nematode symptoms. Cracking of tunic or 

shriveling of fleshy parts may indicate an infection is present. Carefully cut 

or peel away tunic to examine necrotic areas.

4. Peel bulbs with loose tunics to look for nematode and Aceria symptoms.

Pests

Common Pests

Fusarium oxysporum tulipae. Symptoms: Cream colored lesions usually around 

the base and usually forming concentric rings as it expands, accompanied by a 

musty, sour odor.

Mechanical Damage. Symptoms: Blemishes, scars, and abrasions due to injury 

sustained during harvest and cleaning, occurring mostly where the tunic had 

been removed. Such damage can be progressive as the bulb reacts to the injury 

and may sometimes result in chalking. The various forms of mechanical injury 

are often mistaken for Fusarium.

Source: (left photo) PPO; (right photo) USDA-APHIS

Figure 5-95 Fusarium oxysporum tulipae on Tulipa1 2

1 Left photo: left bulb showing Fusarium infection beginning on side of bulb. Right bulb showing 

infection starting at apex. 

2 Right photo: advanced stages of Fusarium.
True Bulbs

Tulipa

5-86 Bulb Identification Manual 10/2011-01

Penicillium. Symptoms: Blue-green mold, often secondary on damaged areas.

Rare Pests

Aceria tulipae. Symptoms: Red, or more rarely, yellow or cream colored 

discoloration depending on flower color, and mealy texture on the surface of 

fleshy scales. In some cases, the discoloration may be very slight, but the 

surface of the bulb, which should be shiny, is dull. Tunic must be partially 

removed to see the symptoms.

Source: USDA-APHIS

Figure 5-96 Mechanical Damage on Tulipa

Source: PPO

Figure 5-97 Penicillium on Damaged Areas of Tulipa
True Bulbs

Tulipa

10/2011-01 Bulb Identification Manual 5-87

Bacterial Snot, Nose Rot. Symptoms: Wet rot on tip of bulb, rot is gray with 

brown border, becoming darker brown with age. In many instances only the 

outer scales are affected. These affected scales usually dry up and become 

“chalked” but the bulb remains healthy. Usually occurs during early stages of 

storage.

Source: (top left and right photos) PPO; (bottom photo) nVWA

Figure 5-98 Aceria tulipae on Tulipa1 2 3

1 Top left photo: Right bulb is healthy; center bulb shows characteristic red discoloration and 

left bulb shows the dull, cream colored discoloration.

2 Top right photo: top bulb is healthy, notice the shiny appearance. Bottom right bulb lacks the 

typical discolorations, but the surface is dull and the bulb is almost totally symptomatic. The 

somewhat vertical streak on the left side of the bulb is due to mechanical damage. Left bottom bulb has two shiny areas at the center and near the apex indicating normal healthy tissue, but the rest of the bulb is dull and affected.

3 Bottom photo: heavily infested bulbs displaying typical symptoms.
True Bulbs

Tulipa

5-88 Bulb Identification Manual 10/2011-01

Chalking. Symptoms: Hard, often chalky outer scales. Chalking is often caused 

when bulbs in the field suffer from lack of oxygen toward the end of the 

growing season and the outer scales begin to rot. When harvested and during 

the drying process, the scales dry out and become chalked. Bulbs suffering 

from nose rot can become chalked.

Source: (top left photo) PPO: (top right and bottom photo) USDA-APHIS

Figure 5-99 Nose Rot on Tulipa1 2 3

1 Top left photo: typical fresh symptoms of nose rot. .

2 Top right photo: bulbs with affected outer scales beginning to dry out.

3 Bottom photo: cross section of bulb showing nose rot damage to outer scales and healthy 

inner scales.
True Bulbs

Tulipa

10/2011-01 Bulb Identification Manual 5-89

Curtobacterium flaccumfasciens pv. oortii. Symptoms: Cracked tunic with yellow 

spots on bulb and yellow rot of fleshy scales. Corynebacterium oortii is a 

synonym.

Source: nVWA

Figure 5-100 Chalking on Tulipa1

1 Characteristic white chalking evident on left two bulbs. Outer scales of right two bulbs are brittle but not chalky white.
True Bulbs

Tulipa

5-90 Bulb Identification Manual 10/2011-01

Rhizoctonia solani. Symptoms: Heavy cracking of tunic with brown-black 

sclerotia originating from the apex of the bulb.

Source: (top photos) BKD: (bottom photo) PPO

Figure 5-101 Tulipa with Curtobacterium flaccumfasciens pv. oortii
True Bulbs

Tulipa

10/2011-01 Bulb Identification Manual 5-91

Sclerotinia bulborum. Symptoms: Black rot that forms sclerotia between scales.

Source: J. Heuperman

Figure 5-102 Rhizoctonia solani on Tulipa

Source: J. Heuperman

Figure 5-103 Sclerotinia bulborum on Tulipa
True Bulbs

Tulipa

5-92 Bulb Identification Manual 10/2011-01

Other Pests

Aphids. Symptoms: Symptoms are not distinctive. To make a rejection, live 

insects must be found. Occurs mostly when bulbs begin to sprout and where 

they have been improperly stored near areas where insects are able to enter the 

warehouse.

Aspergillus. Symptoms: Black mold beneath the tunic. Bulb is also severely 

“chalked.”

Source: PPO

Figure 5-104 Aphids on Tulipa (note gray adult aphids)

Source: USDA-APHIS

Figure 5-105 Aspergillus on Tulipa
True Bulbs

Tulipa

10/2011-01 Bulb Identification Manual 5-93

Botrytis tulipae. Symptoms: Small to large depressed lesions with distinct edges 

and yellowish brown to blackish sclerotia on outer fleshy scales. Lesions run 

together anywhere on bulb.

Ditylenchus destructor. Symptoms: Yellowish to dark brown discoloration 

radiating in streaks from the base. Tunic must be partially removed to see 

symptoms.

Source: PPO

Figure 5-106 Botrytis tulipae on Tulipa

Source: nVWA

Figure 5-107 Ditylenchus destructor on Tulipa1

1 Characteristic streaking from base is evident in the bulb on the right.
True Bulbs

Tulipa

5-94 Bulb Identification Manual 10/2011-01

Ditylenchus dipsaci. Symptoms: Yellowish brown rot radiating fan-like from the 

base. Difficult to distinguish from D. destructor. Samples must be sent in for 

identification.

Gummosis. Symptoms: Clear or amber-like gummy ooze. This is usually a 

physiological reaction to mechanical injury.

Source: nVWA

Figure 5-108 Ditylenchus dipsaci on Tulipa1

1 Infection is well-advanced in bulb on left, with the basal plate almost completely rotted.

Source:

Figure 5-109 Gummosis on Tulipa1

1 Note ooze at apex of bulb.
True Bulbs

Tulipa

10/2011-01 Bulb Identification Manual 5-95

Horse Teeth. Symptoms: A degeneration of the bulb resulting in a proliferation 

of small, non-viable bulblets. In severe cases, the mother bulb degenerates into 

smaller bulbs. To be considered actionable, the mother bulb must comprise less 

than 50 percent of the total mass.

Pseudo-kirkstip. Symptoms: Scab-like lesions on exterior of bulb, with lesions 

on interior. A quality issue; does not affect flowering. Symptoms of pseudokirkstip are very similar to those of Cucumber Mosaic Virus and samples must 

be sent to the laboratory for confirmation. Tulip variety ‘Orange Bouquet’ is 

highly susceptible to pseudo-kirkstip.

Source: USDA-APHIS

Figure 5-110 “Horse Teeth” on Tulipa1

1 Bulb on the right is severely infected.

Source: (left photo) PPO: (right photo) BKD

Figure 5-111 Pseudo-kirkstip on Tulipa1 2
True Bulbs

Tulipa

5-96 Bulb Identification Manual 10/2011-01

Septocylindrium. Symptoms: Outer layer of the outer scales becomes light 

brown. Only occurs on the “belly” side of the bulb. Infections do not progress 

when bulbs are in storage.

Sclerotium tuliparum. Symptoms: Gray or purplish-gray soft rot, usually at the 

nose and affecting the growing shoot. Large brown sclerotia occurring at apex 

of bulb. Causes a dry rot.

No photo available.

Skin Diseases. Symptoms: Physiological disorders manifested by 

discolorations and blemishes that are restricted to the outer leaf scale. If the 

tunic is thin, a grayish tint may be visible through the tunic. Interior of bulb 

remains healthy. There are several types of skin diseases; all are quality, nonphytosanitary disorders.

1 Left photo: cross section of bulbs showing interior symptoms. Bulb on right is affected with 

pseudo-kirkstip. Bulb on right has Cucumber Mosaic Virus..

2 Right photo: exterior symptoms showing dark lesions on outer scales.

Source: PPO

Figure 5-112 Septocylindrium on Tulipa
True Bulbs

Tulipa

10/2011-01 Bulb Identification Manual 5-97

Blue Growth: Symptoms: Symptoms can be mistaken for mechanical damage. 

“Blue Growth” is caused by exceptionally rapid growth during growing 

season.

Source: USDA-APHIS

Figure 5-113 Skin Diseases in Tulipa1 2

1 Left photo: right bulb showing exterior symptoms somewhat resembling those of Fusarium. 

Left bulb showing dried chalky outer scale but healthy interior scales. 

2 Right photo: normally the tunic must be removed to see symptoms; however, symptoms 

might be visible if the tunic is thin. On the right bulb, slight gray tint on the right side indicates 

discoloration of inner scales. Left bulb with gray tint on upper half of bulb.

Source: USDA-APHIS

Figure 5-114 Skin Disease “Blue Growth” in Tulipa
True Bulbs

Tulipa

5-98 Bulb Identification Manual 10/2011-01

Suffocation. Symptoms: Fusarium-like exterior discoloration. The outer scale 

become brittle and the bulb eventually rots from the inside. Interior of bulb has 

a musty-sweet odor. A physiological disorder due to excessively wet growing 

conditions. The bulb is ultimately destroyed, but this is a quality, nonphytosanitary disorder.

Source: USDA-APHIS

Figure 5-115 Suffocation Disorders in Tulipa1

1 Exterior symptoms somewhat resemble skin disease and the outer scales become brittle and 

chalky, but unlike skin diseases, the interior usually rots completely.
True Bulbs

Zephyranthes

10/2011-01 Bulb Identification Manual 5-99

Zephyranthes

Zephyranthes bulbs are teardrop-shaped with a long neck. The bulb is 2–2-1/2 

inches (51–64 mm) long, about three times longer than it is wide. The graybrown tunic is soft and papery or fibrous. The root plate is small. The flesh of 

the bulb is whitish in color, fibrous, and somewhat sticky.

Pest Risk Rating

The pest risk rating for Zephyranthes is 5–6.

Similar Looking Bulbs

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Check for soil contamination and select abnormal bulbs for inspection.

3. Examine outer scales for diseases.

Source: USDA-APHIS

Figure 5-116 Zephyranthes
True Bulbs

Zephyranthes

5-100 Bulb Identification Manual 10/2011-01

4. Examine base for entrance holes of bulb flies.

5. Peel back outer skins to reveal inner fleshy leaves. Red streaking indicates 

Steneotarsonemus.

6. Cut enough of apex to reveal inner fleshy scales. Reddish ring indicates the 

presence of Ditylenchus dipsaci.

Pests

Common Pests

None

Rare Pests

None

Other Pests

Ditylenchus dipsaci. Symptoms: Reddish ring in cross section of neck of bulb.

No photo available.

Fusarium. Symptoms: Brown rot usually beginning at the base of the bulb.

No photo available.

Stagonosporopsis curtisii. Symptoms: Reddish-brown rotting of scales around 

the apex.

No photo available.

Steneotarsonemus laticeps. Symptoms: Reddish pinpoints at edges of scales in 

cross section of neck of bulb; reddish streaks along leaf scales in longitudinal 

section of bulb.

No photo available.
10/2011-01 Bulb Identification Manual 6-1

Chapter

6

Tubers

Contents

Introduction 6-2

Identification Procedure 6-2

Anemone 6-3

Pest Risk Rating 6-3

Similar Looking Tubers 6-3

Inspection Procedures 6-3

Pests 6-4

Arum 6-5

Pest Risk Rating 6-5

Similar Looking Tubers 6-5

Inspection Procedures 6-5

Pests 6-5

Begonia 6-7

Pest Risk Rating 6-7

Similar Looking Tubers 6-7

Inspection Procedures 6-8

Pests 6-8

Cyclamen 6-10

Pest Risk Rating 6-10

Similar Looking Tubers 6-10

Inspection Procedures 6-10

Pests 6-11

Dahlia 6-12

Pest Risk Rating 6-12

Similar Looking Tubers 6-12

Inspection Procedures 6-12

Pests 6-13

Eranthis 6-19

Pest Risk Rating 6-19

Similar Looking Tubers 6-19

Inspection Procedures 6-19

Pests 6-20

Gloriosa 6-21

Pest Risk Rating 6-21

Similar Looking Tubers 6-21

Inspection Procedures 6-21

Pests 6-21
Tubers

Introduction

6-2 Bulb Identification Manual 10/2011-01

Ranunculus 6-24

Pest Risk Rating 6-24

Similar Looking Tubers 6-24

Inspection Procedures 6-24

Pests 6-24

Introduction

Tubers and tuberous roots are swollen underground stems. They grow upright 

or horizontally and are sometimes enlarged at the growing tip. The nodes, or 

eyes, produce new shoots or plants. When tubers grow, they either just expand 

or bud new tubers from the old one.

The information in this chapter includes the pest risk rating for each bulb. The 

ratings are:

Identification Procedure

Determine the length of the bulb you are identifying. Compare it with the 

photographs in this chapter and select the description that fits your bulb. Each 

description includes inspection procedures and pests of concern.

Figure 6-1 Sketch of a Begonia Tuber

Table 6-1 Pest Risk Ratings for Tubers

Pest Risk Rating

1–2 Very low risk. Verify the genus in the shipment. Inspect if time is available

3–4 Low risk. Inspect if time is available

5–6 Moderate risk. Provide normal inspection

7–8 High risk. Inspect thoroughly

9–10 Very high risk. Inspect very thoroughly
Tubers

Anemone

10/2011-01 Bulb Identification Manual 6-3

Anemone

Anemone are small tubers, 0.5–0.75 inches (12–20 mm) in thickness, about 

0.5–1 inch (12–25 mm) across, wrinkled and lumpy and grey-brown to black 

in color. Tubers can be dark and somewhat rounded and lumpy (A. blanda) or 

brown, knobby and lobed (A. coronaria). There are no roots and because the 

tubers are dried, the flesh is very difficult to cut. Very young tubers may be 

shipped. They are called pits and resemble small chocolate chips. Very few 

problems are associated with Anemone. Occasionally, soil can be found on lots 

that are not sufficiently washed.

Pest Risk Rating

The pest risk rating for Anemone is 2.

Similar Looking Tubers

Eranthis is similar in color and size. However, the shape of Eranthis is usually 

rounder and the flesh is easily cut. Eranthis are shipped in the summer. 

Anemone are shipped all year.

Inspection Procedures

Source: USDA-APHIS

Figure 6-2 Anemone coronaria
Tubers

Anemone

6-4 Bulb Identification Manual 10/2011-01

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal tubers for inspection.

3. If the roots are attached, look for knots. Knots indicate Sclerotinia 

tuberosa.

Pests

Common Pests

None

Rare Pests

None

Other Pests

Penicillium. Symptoms: Blue-green mold.

No photo available

Sclerotinia tuberosa. Symptoms: Knots

No photo available
Tubers

Arum

10/2011-01 Bulb Identification Manual 6-5

Arum

Arum are large tubers, 3–6 inches (76–152 mm) in diameter, discoid to 

subglobose, or elongate and very warty in appearance, with a light brown 

color. The roots emerge from the base of the large terminal bud. There is no

root plate.

Pest Risk Rating

The pest risk rating for Arum is 2–3.

Similar Looking Tubers

There are none. The tuberous rhizomes of Zantedeschia are similar.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal tubers for inspection.

3. Squeeze tuber. Softness indicates the presence of Erwinia.

4. Peel back any leaf bases and examine for thrips and aphids.

Pests

Common Pests

None

Source: USDA-APHIS

Figure 6-3 Arum italicum
Tubers

Arum

6-6 Bulb Identification Manual 10/2011-01

Rare Pests

Erwinia aroidea. Symptoms: Soft rot; strong, fetid odor.

Other Pests

Aphids. Symptoms: New buds or shoots may be sticky. Only appears on 

sprouting tubers and when the tubers are stored in areas where insects can gain 

entry into the warehouse.

No photo available

Thrips. Symptoms: Russeting. Only on new growth and where tubers are 

improperly stored.

No photo available

Source: PPO

Figure 6-4 Advanced Stages of Erwinia aroidea Infection on Arum italicum
Tubers

Begonia

10/2011-01 Bulb Identification Manual 6-7

Begonia

Begonia tubers are lumpy, subglobose or discoid, fleshy structures varying in 

diameter from 1.2–4 inches (32–102 mm). There is normally a depression at 

the apex where the buds emerge. Normally, the tuber would be covered by a 

dense mat of roots, but most of the roots are usually removed during cleaning. 

Soil or growing media can be occasionally found in the mat of roots or in the 

apical depression. The tuber lacks a root plate. Storage rot and soil are the most 

common causes of rejection in Begonia.

Pest Risk Rating

The pest risk rating for Begonia is 3–4.

Similar Looking Tubers

Gloxinia is similar.

Source: USDA-APHIS

Figure 6-5 Begonia
Tubers

Begonia

6-8 Bulb Identification Manual 10/2011-01

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination in the apical depression and in the dense mat 

of roots and select abnormal tubers for inspection.

3. Squeeze tuber. Softness and wrinkled, sunken edges on the tuber may 

indicate disease or storage rot.

4. Look at roots and root scars for symptoms of nematodes.

Pests

Common Pests

Storage Rot. Symptoms: Soft rot but lacking fetid odor. Discoloration of tissue. 

The main cause of storage rot are Pythium and Phytophthora.

Rare Pests

Botrytis. Symptoms: Soft rot with white to gray mycelia.

Source: USDA-APHIS

Figure 6-6 Cross Sections of Begonia Showing Examples of Storage Rot 1

1 The tuber on the right is healthy; tubers in center and left suffer from storage rot.
Tubers

Begonia

10/2011-01 Bulb Identification Manual 6-9

Other Pests

Erwinia. Symptoms: Soft rot and fetid odor.

Source: BKD

Figure 6-7 Botrytis on Begonia

Source: PPO

Figure 6-8 Erwinia chrysanthii on Begonia
Tubers

Cyclamen

6-10 Bulb Identification Manual 10/2011-01

Cyclamen

Cyclamen are flattened, subglobose or discoid tubers varying in size from 1–5 

inches (2.5–12.5 cm) in diameter. They are dark red-brown to brown in color 

with smooth, leathery, rough, or wrinkled skin. The flesh is potato-like. The 

roots are fibrous, emerging from the bottom, sides, or near the top of the tuber 

depending on species. There are no serious problems with Cyclamen.

Pest Risk Rating

The pest risk rating for Cyclamen is 3–4.

Similar Looking Tubers

Gloxinia may resemble in size and shape, but the Gloxinia skin is easier to cut.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal tubers for inspection.

Source: USDA-APHIS

Figure 6-9 Three Different Species of Cyclamen
Tubers

Cyclamen

10/2011-01 Bulb Identification Manual 6-11

3. Squeeze the tuber. Softness and wrinkled, shrunken edges on the tuber may 

indicate disease.

4. Examine for disease and borer tunneling.

5. Examine roots and root scars for nematode symptoms.

Pests

Common Pests

None

Rare Pests

Botrytis cinerea. Symptoms: Gray mold and brown wet decay of tissue.

Other Pests

None

Source: BKD

Figure 6-10 Botrytis cinerea on Cyclamen
Tubers

Dahlia

6-12 Bulb Identification Manual 10/2011-01

Dahlia

Dahlia has a root crown with a cluster of pendulous, spindle-shaped or fat 

tubers attached to the nodes of the stem. The flesh is white or yellow. Some 

varieties have densely clustered tubers that may trap soil or weeds. Soil and 

weeds are the most frequent reasons for rejection in Dahlia.

Pest Risk Rating

The pest risk rating for Dahlia is 7–8.

Similar Looking Tubers

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and weeds, and select abnormal tubers for 

inspection, especially those with tumors or growths.

3. Examine crown for galls.

4. Examine fleshy roots and root crown.

Source: USDA-APHIS

Figure 6-11 Dahlia
Tubers

Dahlia

10/2011-01 Bulb Identification Manual 6-13

Pests

Common Pests

Meloidogyne. Symptoms: Watery, brown spots developing into bumps or 

swelling on roots.

Rhodococcus fasciens. Symptoms: Spongy cauliflower-like fasciations usually 

at the root crown.

Source: PPO

Figure 6-12 Dahlia with Characteristic Swellings of Meloidogyne
Tubers

Dahlia

6-14 Bulb Identification Manual 10/2011-01

Top rot (wet rot; water damage). Symptoms: Progressive wet rot beginning at the 

stem and continuing into the root crown and causing decay where the new 

shoots would emerge. Caused by insufficient drying after harvest.

Source: (left photo) PPO; (right photo) USDA-APHIS

Figure 6-13 Examples of Dahlia Infected with R. fasciens1 2

1 Left photo: The Dahlia on the left is infected with Agrobacterium tumefasciens, the Dahlia on 

the right is infected with Rhodococcus fasciens.

2 Right photo: Dahlia with R. fasciens emerging from between the tubers.

Source: USDA-APHIS

Figure 6-14 Dahlia with Top Rot1

1 In this photo, the long fibers are the fibrous remnants of old roots and tubers.
Tubers

Dahlia

10/2011-01 Bulb Identification Manual 6-15

Rare Pests

Agrobacterium tumefasciens. Symptoms: Small to large tumors, usually at the 

crown. Tumors are smooth and often resemble the tuberous roots but lack roots 

of their own.

Frost Damage. Symptoms: Softness of tubers and discoloration of flesh.

Source: PPO

Figure 6-15 Agrobacterium tumefasciens on Dahlia

Source: PPO

Figure 6-16 Frost Damage on Dahlia1
Tubers

Dahlia

6-16 Bulb Identification Manual 10/2011-01

Penicillium. Symptoms: Blue-green mold. Generally caused by insufficient 

drying and improper storage conditions.

Other Pests

Ditylenchus destructor. Symptoms: Linear cracking and necrosis of tubers.

1 The sample on the left is healthy; the sample on the right shows typical discoloration from 

frost damage.

Source: USDA-APHIS

Figure 6-17 Penicillium on Dahlia
Tubers

Dahlia

10/2011-01 Bulb Identification Manual 6-17

Erwinia. Symptoms: Soft rot, normally with fetid odor.

Sclerotinia sclerotiorium. Symptoms: Soft rot with fuzzy white mycelia and black 

sclerotia. 

Source: PPO

Figure 6-18 Ditylenchus destructor on Dahlia1

1 The sample on the left is severely infected; blackened tuberous roots are already deteriorating. The sample on the right shows linear cracking of the tuberous roots.

Source: PPO

Figure 6-19 Erwinia on Dahlia
Tubers

Dahlia

6-18 Bulb Identification Manual 10/2011-01

Source: PPO

Figure 6-20 Advanced Stage of Sclerotinia sclerotiorium Infection in Dahlia 1

1 The specimen is already deteriorating; note white mycelia.
Tubers

Eranthis

10/2011-01 Bulb Identification Manual 6-19

Eranthis

Eranthis tubers are small in size, about 0.25–0.5 inches (6–13 mm) thick, and 

0.5–.75 inches (13–19 mm) in diameter. They are usually round, flattened, 

grey-brown to black in color, and wrinkled but easily cut. The basal root plate 

may be small and show a few roots. They are shipped in the early summer. 

There are no serious problems with Eranthis.

Pest Risk Rating

The pest risk rating for Eranthis is 2.

Similar Looking Tubers

Both Anemone and Eranthis are the same color and texture. However, 

Anemone tubers are extremely hard and Eranthis are somewhat more fleshy. 

Eranthis tend to be plumper than Anemone. Anemone are shipped all year. 

Eranthis are shipped in the summer.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal tubers for inspection.

Source: USDA-APHIS

Figure 6-21 Eranthis
Tubers

Eranthis

6-20 Bulb Identification Manual 10/2011-01

3. Examine tuber for disease symptoms.

Pests

Common Pests

None

Rare Pests

Fusarium. No photo available.

Penicillium. Symptoms: Blue-green mold. 

No photo available.

Other Pests

None
Tubers

Gloriosa

10/2011-01 Bulb Identification Manual 6-21

Gloriosa

Gloriosa tubers resemble a long, thin potato with smooth, light brown skin. 

The tuber is white and fleshy. Gloriosa is occasionally shipped in the winter.

Pest Risk Rating

The pest risk rating for Gloriosa is 3.

Similar Looking Tubers

Tubers of Littonia are similar, but are irregular in shape.

Inspection Procedures

1. Check consignment and verify lot.

2. Check for soil contamination and select abnormal tubers for inspection.

3. Examine outer skin for disease.

Pests

Common Pests

None

Rare Pests

None

Source: USDA-APHIS

Figure 6-22 Gloriosa
Tubers

Gloriosa

6-22 Bulb Identification Manual 10/2011-01

Other Pests

Erwinia. Symptoms: Soft brown rot accompanied by a fetid odor.

Phytophthora. Symptoms: Brown to black wet rot with no fetid odor. 

Penicillium. Symptoms: Blue-green mold.

Source: PPO

Figure 6-23 Erwinia and Phytophthora on Gloriosa

Source: PPO

Figure 6-24 Penicillium on Gloriosa Tubers 
Tubers

Gloriosa

10/2011-01 Bulb Identification Manual 6-23

Rhizoglyphus. Symptoms: Large secondary mites found in decaying tissue. 

Mites will also tunnel into the tubers forming small, disjointed channels. This 

is mostly a storage problem.

Rhodococcus. Symptoms: Tumor-like fasciations along the root.

Source: PPO

Figure 6-25 Rhizoglyphus in Gloriosa

Source: PPO

Figure 6-26 Rhodococcus on Gloriosa
Tubers

Ranunculus

6-24 Bulb Identification Manual 10/2011-01

Ranunculus

Ranunculus are very distinctive. They are small brown tubers, 0.75–1 inch 

(20–25 mm) in length, and appear as a tiny cluster of hard fleshy roots, topped 

with a hairy crown and three to five minute buds. When dried, they shrink to 

nearly half the size and become hardened. There are no phytosanitary problems 

with Ranunculus.

Pest Risk Rating

The pest risk rating for Ranunculus is 2–3.

Similar Looking Tubers

There are none.

Inspection Procedures

1. Check consignment and verify lot.

2. Look for soil contamination and select abnormal tubers for inspection.

3. Examine crown and tubers for disease symptoms.

Pests

Source: USDA-APHIS

Figure 6-27 Ranunculus
Tubers

Ranunculus

10/2011-01 Bulb Identification Manual 6-25

Common Pests

None

Rare Pests

None

Other Pests

None
Tubers

Ranunculus

6-26 Bulb Identification Manual 10/2011-01
10/2011-01 Bulb Identification Manual Glossary-1

Bulb 

Identification 

Glossary

Use this glossary to find the meaning of specialized words, abbreviations, 

acronyms, and terms used by USDA-APHIS-PPQ-IRM-Information Services 

and Manuals Unit. To locate where in the manual a given definition, term, or 

abbreviation is mentioned, refer to the Index.

Definitions, Terms, and Abbreviations

annulate tunic. a tunic provided with or composed of rings

axil/axillary. (a) the upper angle that a lateral organ, such as a petiole or 

peduncle, makes with the axis or stem that bears it (b) angle between the upper 

surface of a leaf and the stem

axillary bud. bud originating in the leaf axil

BKD. Bloembollenkeuringsdeinst

corm. (a) a solid, swollen part of a stem, usually subterranean (b) short, 

vertical underground stem surrounded by thin, papery leaves

discoid. having a disc-shaped, flat, circular form

fasciated/fasciations. abnormally flattened or coalesced as in certain stems

globose. spherical, shaped like a globe

internode. the part of a stem between two adjacent nodes

mycelium. the vegetative part of a fungus

nVWA. the Dutch Plant Protection Service

node. point along the stem from which the leaves and buds arise

ovoid. shaped like an egg

PDC. the USDA APHIS Professional Development Center

PPO. the Applied Plant Research Station in Lisse, Holland

perennial. a plant that lives three years or more, tending to flower and fruit 

repeatedly

reticulate/reticulation. netted; net like

rhizome. a horizontal stem, usually underground

sori. clusters of sporangia

true bulb. 
Glossary

Definitions, Terms, and Abbreviations 

Glossary-2 Bulb Identification Manual 10/2011-01

tuber. a thick, fleshy, underground part of a stem that serves as a storage organ

tunic. a loose, membranous, outer skin not the epidermis, especially the loose 

membrane around a corm or bulb

vascular bundle. a collective term for tissue containing xylem and phloem, 

usually surrounded by a sheath of parenchyma cells
10/2011-01 Bulb Identification Manual Index-1

Bulb 

Identification 

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Y

Z

Index

A

Acidanthera

general information 2-5

pests of

Fusarium 2-8

thrips 2-8

Aconitum 3-6

Agapanthus 3-10

Allium 5-6

Anemone 3-12, 6-3

Aquilegia 3-14

Arum 6-5

Aruncus 3-16

Astilbe 4-3

Astrantia 3-19

B

Babiana 2-7

Begonia 6-7

Brodiaea 2-9

C

Camassia 5-13

Campanula 3-21

Canna 4-6

Chionodoxa 5-15

Colchicum 2-11

Convallaria 4-8

corms 2-1

Crocosmia 2-15

Crocus 2-18

Cyclamen 6-10

D

Dahlia 6-12

Dicentra 3-24

E

Echinacea 3-27

Epimedium 3-29

Eranthis 6-19

Eremurus 3-33

Eryngium 3-35

F

Freesia 2-25

Fritillaria 5-18

G

Galanthus 5-22

Galtonia 5-25

Geranium 3-37

Gladiolus 2-33

Gloriosa 6-21

glossary Glossary-1

H

Hemerocallis 4-10

Heuchera 3-41

Hippeastrum 5-27

Hosta 3-44

Hyacinthus 5-32

I

Incarvillea 3-48

Iris 4-12, 5-40

Ixia 2-46

L

Liatris 3-51

Ligularia 3-54

Lilium 5-47

M

Muscari 5-54

N

Narcissus 5-58

O

Ornithogalum 5-67

Oxalis 5-70

P

Paeonia 4-14

Papaver 3-57

perennials 3-1

pest risk rating

corms 2-4

perennials 3-5

rhizomes 4-2

true bulbs 5-5

tubers 6-2

Phlox 3-61

Platycodon 3-66

Pulmonaria 3-69

Puschkinia 5-72

R

Ranunculus 6-24

rhizomes 4-1

Rudbeckia 3-71

S

Salvia 3-73

Scilla 5-75

Sparaxis 2-48

Sprekelia 5-79

T

Tigridia 5-81
Index

 

Index-2 Bulb Identification Manual 10/2011-01

Tradescantia 3-75

true bulbs 5-1

tubers 6-1

Tulipa 5-84

V

Veronica 3-77

Z

Zantedeschia 4-18

Zephyranthes 5-99